WebView2 Deployment

Question

WebView2 Deployment

Hal Roenick 20

Hello,

I recently converted a VB.net (VS 2022) Desktop Application from a WebBrowser control to a WebView2 Control. I have everything working just as I would like. When I create an installer and include all of the dependencies then install my application, the application will not display the form that has the WebView2 control on it and I get this error...

Microsoft.Web.WebView2.WinForms, Version=1.0.4071.0, Culture=neutral, PublicKeyToken=2a8ab48044d2601e' or one of its dependencies. The system cannot find the file specified.

When I look up this error, it tells me I am missing a dependency, but I have created a setup and included all of the dependencies. I have also tried to install the Evergreen version of the WebView2 files and that installer tells me all the WebView2 dependencies are already installed on my PC. Does anyone have a suggestion?

Thank you.

Hal Roenick 20 Reputation points

2026-07-06T18:25:16.69+00:00
Hello everyone and thank you for the replies and ideas on this topic. With the help of a friend, we seem to have figured out where the problem is/was...Please understand that I am a self taught programmer and not nearly as proficient as most who likely replied to my post, so please let me know if you see something wrong with my assessment, but this is what we found.

My experience has led me to believe that Microsoft recommends that 64 bit executable programs be installed in the Program Files (x86) folder. I have run this application at 32 bit and 64 bit in that folder for almost 15 years with no issues. Shortly after I posted this issue to this list, I put the "Await WebView21.EnsureCoreWebView2Async(Nothing)" statement into its own Try/Catch statement that I found on the web and started capturing a different error that told me that the program could not "write to the folder where the program is installed". This even though I knew the program needed to be told not to write in the folder where the .exe resides, but to point it to the users AppDataPath as shown here...

Dim userDataFolder As String = System.IO.Path.Combine(Application.LocalUserAppDataPath, "EBWebView")

Dim environment As Microsoft.Web.WebView2.Core.CoreWebView2Environment =

Await Microsoft.Web.WebView2.Core.CoreWebView2Environment.CreateAsync(Nothing, userDataFolder, Nothing)

Once I changed my installation and installed my application in a folder in the root directory of the system drive, everything started working correctly. It seems the setting I tried to make above did not keep the program from writing data to the executables directory.

One other thing that I found that was quite interesting...I have a routine in my application where a list of files that reside on-line are printed one by one automatically. The user has the ability to decide how many copies of each of those files gets printed in the "Auto Print" routine. In my earlier version of this App, the list was made in a Datagridview that resided in a different dialog than where the WebBrowser control existed, but was then each file was navigated to in the WebBrowser control for automatic printing. I found that the WebView2 control would lose it instance meaning the "WebView21.CoreWebView2" instance would become "Nothing" when the new dialog with the DGV was displayed. So, I ended up putting a new DGV onto the same dialog as the WebView2 control and simply set its "Visible" property to "False", then set it to "True" via a button in a toolbar above where the WebView2 and DGV are displayed to control the printing of those files.

So basically what I found is, two Don'ts when using a WebView2 control...

Deploy your project to a folder where Windows does not have a problem with your reading and writing to files.

Do not try to use controls outside the dialog where the WebView2 resides to do any processing that needs to interact with the WebView2 control.

Thank you again for your help and let me know if you know of a better way to resolve the issues I have described. Everyone's posts were correct in things that needed to be done, but were not what fixed my issues. I had all of the correct Prerequisites in my install program, changing the path where it was installed was the real answer, at least for me.

Answer accepted by question author

Nancy Vo (WICLOUD CORPORATION) 8,155 Microsoft External Staff Moderator

Hello @Hal Roenick ,

Thank you so much for sharing your findings.

Since you cannot accept your own answer, I’m posting this issue and its solution to help anyone else who may encounter the same problem.

In addition to the solutions you found, I recommend an additional workaround to help keep your application aligned with standard Windows security practices:

Managing the installation folder and permissions.

Moving the application to the root of the system drive bypasses Windows security, but it is much safer to keep 32-bit apps in the standard Program Files (x86) folder. You can refer to these code example:

Dim userDataFolder As String = System.IO.Path.Combine(Application.LocalUserAppDataPath, "EBWebView")

Dim environment As Microsoft.Web.WebView2.Core.CoreWebView2Environment = Await Microsoft.Web.WebView2.Core.CoreWebView2Environment.CreateAsync(Nothing, userDataFolder, Nothing)

Await WebView21.EnsureCoreWebView2Async(environment)

If you ever want to move your DataGridView back to a separate dialog, you absolutely can. When WebView2 turns into Nothing in VB.NET, it is usually because the code accidentally called a "ghost" copy of the form instead of the real one you are looking at. Passing a direct reference of your open form to the new dialog will prevent the control from losing its instance.

Again, thank you so much for sharing your time and experience.

If any part of my explanation helped address your question, I would greatly appreciate it if you could follow the instructions here. This can also help other community members facing similar scenarios.

Hal Roenick 20 Reputation points

2026-07-07T16:36:23.71+00:00

Yes please, can you explain how to Pass a direct reference of your open form to the new dialog as you suggested?
Hal Roenick 20 Reputation points

2026-07-07T17:26:03.5433333+00:00

Can you explain how to Pass a direct reference of my open form to the new dialog?
Nancy Vo (WICLOUD CORPORATION) 8,155 Reputation points Microsoft External Staff Moderator

2026-07-08T04:06:33.9533333+00:00
Hi @Hal Roenick ,

Passing a reference simply means telling your new dialog exactly which main screen to talk to, so it doesn't accidentally create a blank "ghost" copy in the background.

You can refer to these following steps:

Open the code for your new dialog (the one with the DataGridView). Add a variable to hold the main form, and update the Sub New (the constructor) to accept it:

Public Class DialogForm Private _mainForm As Form1 Public Sub New(ByVal callingForm As Form1) InitializeComponent() _mainForm = callingForm End Sub End Class

Whenever you need to make the WebView2 control do something from this new dialog, always use your new _mainForm variable instead of the default form name:

Private Sub PrintButton_Click(sender As Object, e As EventArgs) Handles PrintButton.Click _mainForm.WebView21.CoreWebView2.Navigate("https://www.example.com") End Sub

Finally, back on your Main Form, when you click the button to open the new dialog, put Me inside the parentheses. Me is VB.NET's way of saying "pass this exact screen."

Private Sub OpenDialogButton_Click(sender As Object, e As EventArgs) Handles OpenDialogButton.Click Dim myDialog As New DialogForm(Me) myDialog.Show() End Sub

Hope this helps. Thanks for your time.
Hal Roenick 20 Reputation points

2026-07-08T19:18:29.74+00:00

Nancy,

Your suggestion of Passing a reference seems to have worked to some extent. The way I have this "Auto Print" system setup is that the Dialog with the DGV is only used to create an ArrayList of Print Commands. That Dialog then sends the list of Print Commands to a Public Function in the Main dialog (where the WebView2 is ) as a parameter, then the main dialog deals with the list and Navigates to and prints each document from the ArrayList.

Prior to today, what I had done was create a DGV that was hidden most of the time on the Main Dialog, then displayed when necessary instead of the Auto Print Dialog and that DGV was used by the Main Dialog to create the same ArrayList and call the same Function. When I had the DGV on the same Dialog as the WebView2, I could physically see each Web Page being navigated to and of course the actual printing is done behind the scenes. Now, with the DGV back on the Auto Print Dialog, everything gets printed just fine, but I cannot see the navigation taking place. This even though I use WebView21.Refresh() after each web page is loaded using WebView21.Source = New Uri(sPath & "?t=" & DateTimeOffset.UtcNow.ToUnixTimeMilliseconds()).

Any ideas on making it so I can see the navigation or why I cannot see it?

Thank you.
Nancy Vo (WICLOUD CORPORATION) 8,155 Reputation points Microsoft External Staff Moderator

2026-07-09T04:32:39.3266667+00:00
Hi @Hal Roenick ,

The issue is that your loop is running so fast it is blocking the UI thread. The application is so busy processing the list that it never pauses to visually update the screen, even when you call Refresh().

I recommend changing your printing function to be Async and adding a small delay inside your loop. This yields the thread back to Windows just long enough to draw the WebView2 navigation.

Update your public function on the main dialog:

Public Async Function ProcessPrintCommands(ByVal printList As ArrayList) As Task For Each item In printList WebView21.Source = New Uri(sPath & "?t=" & DateTimeOffset.UtcNow.ToUnixTimeMilliseconds()) Await Task.Delay(500) Next End Function

Update the button on your auto print dialog:

Private Async Sub StartPrintingButton_Click(sender As Object, e As EventArgs) Handles StartPrintingButton.Click Await _mainForm.ProcessPrintCommands(myArrayList) End Sub

I hope you find this information useful. Thank you.
Hal Roenick 20 Reputation points

2026-07-09T11:21:39.7366667+00:00

Nancy,

Thank you but that does not seem to be the problem. I already tried your suggestion along with forcing a paint on the Webview2 also...

WebView21.Invalidate() ' Marks the control as needing repaint

WebView21.Update() ' Forces immediate repaint

Again, when the DGV is in the same dialog, I can see each page displayed, I have a wait of 1000 in the loop already for that purpose. Something is keeping the WebView2 from rendering. It seems like it has something to do with the WebView2 or its parent loosing focus or something like that. It almost seems like the navigation must be taking place in a different instance of the WebView2 because everything works, I just cannot see it.

BTW, I also set a navigation bar text to show each item being opened and I can see that happening about 1 per second.
Nancy Vo (WICLOUD CORPORATION) 8,155 Reputation points Microsoft External Staff Moderator

2026-07-10T08:12:10.33+00:00
Hi,

Thanks for your update.

In VB.NET, if you trigger a control on your main form from a second dialog by just using the form's default name (like MainForm.WebView21.Navigate), VB.NET implicitly creates a brand new, invisible "ghost" instance of that main form.

I suggest passing the actual open instance of your main form to your new dialog so they can talk to each other properly.

In the code for your dialog with the DataGridView, update the constructor (Sub New) to accept the main form:

Private _mainForm As Form1 ' Public Sub New(ByVal callingForm As Form1) InitializeComponent() _mainForm = callingForm End Sub

When you trigger the navigation from that dialog, use your new variable instead of the default form name:

_mainForm.WebView21.CoreWebView2.Navigate(url)

PLese it give it a try and let me know how it goes. Again, thanks for your time.
Hal Roenick 20 Reputation points

2026-07-10T14:03:03.94+00:00
Nancy,

Bingo! As I mentioned, I was not controlling the action in the webView2 directly from the Auto Print dialog but from a function ( ExecuteAutoPrint )in the Main dialog. Once I used the _mainForm. to call it rather than the Form name, It all works...

If MyList.Count > 0 Then

_mainForm.ExecuteAutoPrint(MyList)

Else

MB("No list of files to print was generated from grid")

End If

Thank you very much, this was best experience I have had with a Microsoft Tech, you were very helpful and patient.
Nancy Vo (WICLOUD CORPORATION) 8,155 Reputation points Microsoft External Staff Moderator

2026-07-13T02:34:27.85+00:00

Thanks so much for your feedback. I hope I was able to provide helpful information.

4 additional answers

Your answer

Hal Roenick 20 Reputation points

2026-07-07T16:36:23.71+00:00

Yes please, can you explain how to Pass a direct reference of your open form to the new dialog as you suggested?
Hal Roenick 20 Reputation points

2026-07-07T17:26:03.5433333+00:00

Can you explain how to Pass a direct reference of my open form to the new dialog?
Nancy Vo (WICLOUD CORPORATION) 8,155 Reputation points Microsoft External Staff Moderator

2026-07-08T04:06:33.9533333+00:00

Hi @Hal Roenick ,

Passing a reference simply means telling your new dialog exactly which main screen to talk to, so it doesn't accidentally create a blank "ghost" copy in the background.

You can refer to these following steps:

Open the code for your new dialog (the one with the DataGridView). Add a variable to hold the main form, and update the Sub New (the constructor) to accept it:

Public Class DialogForm Private _mainForm As Form1 Public Sub New(ByVal callingForm As Form1) InitializeComponent() _mainForm = callingForm End Sub End Class

Whenever you need to make the WebView2 control do something from this new dialog, always use your new _mainForm variable instead of the default form name:

Private Sub PrintButton_Click(sender As Object, e As EventArgs) Handles PrintButton.Click _mainForm.WebView21.CoreWebView2.Navigate("https://www.example.com") End Sub

Finally, back on your Main Form, when you click the button to open the new dialog, put Me inside the parentheses. Me is VB.NET's way of saying "pass this exact screen."

Private Sub OpenDialogButton_Click(sender As Object, e As EventArgs) Handles OpenDialogButton.Click Dim myDialog As New DialogForm(Me) myDialog.Show() End Sub

Hope this helps. Thanks for your time.
Hal Roenick 20 Reputation points

2026-07-08T19:18:29.74+00:00

Nancy,

Your suggestion of Passing a reference seems to have worked to some extent. The way I have this "Auto Print" system setup is that the Dialog with the DGV is only used to create an ArrayList of Print Commands. That Dialog then sends the list of Print Commands to a Public Function in the Main dialog (where the WebView2 is ) as a parameter, then the main dialog deals with the list and Navigates to and prints each document from the ArrayList.

Prior to today, what I had done was create a DGV that was hidden most of the time on the Main Dialog, then displayed when necessary instead of the Auto Print Dialog and that DGV was used by the Main Dialog to create the same ArrayList and call the same Function. When I had the DGV on the same Dialog as the WebView2, I could physically see each Web Page being navigated to and of course the actual printing is done behind the scenes. Now, with the DGV back on the Auto Print Dialog, everything gets printed just fine, but I cannot see the navigation taking place. This even though I use WebView21.Refresh() after each web page is loaded using WebView21.Source = New Uri(sPath & "?t=" & DateTimeOffset.UtcNow.ToUnixTimeMilliseconds()).

Any ideas on making it so I can see the navigation or why I cannot see it?

Thank you.
Nancy Vo (WICLOUD CORPORATION) 8,155 Reputation points Microsoft External Staff Moderator

2026-07-09T04:32:39.3266667+00:00

Hi @Hal Roenick ,

The issue is that your loop is running so fast it is blocking the UI thread. The application is so busy processing the list that it never pauses to visually update the screen, even when you call Refresh().

I recommend changing your printing function to be Async and adding a small delay inside your loop. This yields the thread back to Windows just long enough to draw the WebView2 navigation.

Update your public function on the main dialog:

Public Async Function ProcessPrintCommands(ByVal printList As ArrayList) As Task For Each item In printList WebView21.Source = New Uri(sPath & "?t=" & DateTimeOffset.UtcNow.ToUnixTimeMilliseconds()) Await Task.Delay(500) Next End Function

Update the button on your auto print dialog:

Private Async Sub StartPrintingButton_Click(sender As Object, e As EventArgs) Handles StartPrintingButton.Click Await _mainForm.ProcessPrintCommands(myArrayList) End Sub

I hope you find this information useful. Thank you.
Hal Roenick 20 Reputation points

2026-07-09T11:21:39.7366667+00:00

Nancy,

Thank you but that does not seem to be the problem. I already tried your suggestion along with forcing a paint on the Webview2 also...

WebView21.Invalidate() ' Marks the control as needing repaint

WebView21.Update() ' Forces immediate repaint

Again, when the DGV is in the same dialog, I can see each page displayed, I have a wait of 1000 in the loop already for that purpose. Something is keeping the WebView2 from rendering. It seems like it has something to do with the WebView2 or its parent loosing focus or something like that. It almost seems like the navigation must be taking place in a different instance of the WebView2 because everything works, I just cannot see it.

BTW, I also set a navigation bar text to show each item being opened and I can see that happening about 1 per second.
Nancy Vo (WICLOUD CORPORATION) 8,155 Reputation points Microsoft External Staff Moderator

2026-07-10T08:12:10.33+00:00

Hi,

Thanks for your update.

In VB.NET, if you trigger a control on your main form from a second dialog by just using the form's default name (like MainForm.WebView21.Navigate), VB.NET implicitly creates a brand new, invisible "ghost" instance of that main form.

I suggest passing the actual open instance of your main form to your new dialog so they can talk to each other properly.

In the code for your dialog with the DataGridView, update the constructor (Sub New) to accept the main form:

Private _mainForm As Form1 ' Public Sub New(ByVal callingForm As Form1) InitializeComponent() _mainForm = callingForm End Sub

When you trigger the navigation from that dialog, use your new variable instead of the default form name:

_mainForm.WebView21.CoreWebView2.Navigate(url)

PLese it give it a try and let me know how it goes. Again, thanks for your time.
Hal Roenick 20 Reputation points

2026-07-10T14:03:03.94+00:00

Nancy,

Bingo! As I mentioned, I was not controlling the action in the webView2 directly from the Auto Print dialog but from a function ( ExecuteAutoPrint )in the Main dialog. Once I used the _mainForm. to call it rather than the Form name, It all works...

If MyList.Count > 0 Then

_mainForm.ExecuteAutoPrint(MyList)

Else

MB("No list of files to print was generated from grid")

End If

Thank you very much, this was best experience I have had with a Microsoft Tech, you were very helpful and patient.
Nancy Vo (WICLOUD CORPORATION) 8,155 Reputation points Microsoft External Staff Moderator

2026-07-13T02:34:27.85+00:00

Thanks so much for your feedback. I hope I was able to provide helpful information.

Answer 1

Hello everyone and thank you for the replies and ideas on this topic. With the help of a friend, we seem to have figured out where the problem is/was...Please understand that I am a self taught programmer and not nearly as proficient as most who likely replied to my post, so please let me know if you see something wrong with my assessment, but this is what we found.

My experience has led me to believe that Microsoft recommends that 64 bit executable programs be installed in the Program Files (x86) folder. I have run this application at 32 bit and 64 bit in that folder for almost 15 years with no issues. Shortly after I posted this issue to this list, I put the "Await WebView21.EnsureCoreWebView2Async(Nothing)" statement into its own Try/Catch statement that I found on the web and started capturing a different error that told me that the program could not "write to the folder where the program is installed". This even though I knew the program needed to be told not to write in the folder where the .exe resides, but to point it to the users AppDataPath as shown here...

Dim userDataFolder As String = System.IO.Path.Combine(Application.LocalUserAppDataPath, "EBWebView")

Dim environment As Microsoft.Web.WebView2.Core.CoreWebView2Environment =

Await Microsoft.Web.WebView2.Core.CoreWebView2Environment.CreateAsync(Nothing, userDataFolder, Nothing)

Once I changed my installation and installed my application in a folder in the root directory of the system drive, everything started working correctly. It seems the setting I tried to make above did not keep the program from writing data to the executables directory.

One other thing that I found that was quite interesting...I have a routine in my application where a list of files that reside on-line are printed one by one automatically. The user has the ability to decide how many copies of each of those files gets printed in the "Auto Print" routine. In my earlier version of this App, the list was made in a Datagridview that resided in a different dialog than where the WebBrowser control existed, but was then each file was navigated to in the WebBrowser control for automatic printing. I found that the WebView2 control would lose it instance meaning the "WebView21.CoreWebView2" instance would become "Nothing" when the new dialog with the DGV was displayed. So, I ended up putting a new DGV onto the same dialog as the WebView2 control and simply set its "Visible" property to "False", then set it to "True" via a button in a toolbar above where the WebView2 and DGV are displayed to control the printing of those files.

So basically what I found is, two Don'ts when using a WebView2 control...

Deploy your project to a folder where Windows does not have a problem with your reading and writing to files.
Do not try to use controls outside the dialog where the WebView2 resides to do any processing that needs to interact with the WebView2 control.

Thank you again for your help and let me know if you know of a better way to resolve the issues I have described. Everyone's posts were correct in things that needed to be done, but were not what fixed my issues. I had all of the correct Prerequisites in my install program, changing the path where it was installed was the real answer, at least for me.

Answer 2

Hal Roenick 20

From what I can tell, all of the references mentioned above are installed on my system after I have installed my application. For example, WebView2Loader.dll is installed in all 3 of the runtimes folders mentioned (win-X86, win- X64 and win-arm64) in my application. My application is set to Any PC. As I mentioned above, my application works fine in the Visual Studio environment, but as soon as I deploy it and install it on my system, the problem persists.

The WebView2Loader.dll files are loaded in this path...

C:\Program Files (x86)\VCAMM Software\Golf League Pro\runtimes\win-x64\native

...and the .exe of my application is in this folder...C:\Program Files (x86)\VCAMM Software\Golf League Pro

Thank you

Hal Roenick 20 Reputation points

2026-07-04T14:10:57.5266667+00:00

I posted this "answer" above as though it was an answer, but it was actually a response to the AI suggested solution to my problem, but as you can see, the suggested solution did not work.

Answer 3

The error indicates that the Microsoft.Web.WebView2.WinForms assembly (or one of its dependencies) is not being deployed with the application, even though the development machine has the Evergreen WebView2 Runtime installed.

Two separate things must be present on the target machine:

WebView2 Runtime (Evergreen or Fixed Version)
WebView2 loader and .NET assemblies that your app directly references

The Evergreen Runtime installer only installs the runtime, not the assemblies your app must ship.

To fix deployment for a VB.NET WinForms app:

Ensure WebView2 loader DLL is included
For .NET managed apps, WebView2Loader.dll is a native, architecture-specific binary and must be shipped with the app:
```
   \<myApp>
       \runtimes
           \win-arm64\native\WebView2Loader.dll (arm64)
           \win-x64\native\WebView2Loader.dll (x64)
           \win-x86\native\WebView2Loader.dll (x86)
```
In Visual Studio Installer/Setup Project, explicitly add these files from the WebView2 SDK output (usually under runtimes\win-<arch>\native).
Include the WebView2 .NET assemblies
For a WinForms app, the following assemblies must be deployed alongside the EXE:
```
   Microsoft.Web.WebView2.Core.dll
   Microsoft.Web.WebView2.Winforms.dll
```
Confirm that:
- They appear in the app’s output folder on the build machine.
- They are added as files in the installer project and installed to the same folder as your application EXE.
Verify architecture alignment
Make sure the architecture of:
- Your app (x86/x64/AnyCPU),
- WebView2Loader.dll variants,
- And the installed WebView2 Runtime are consistent. For AnyCPU, include x86, x64, and arm64 loader DLLs under runtimes as shown above.
If using Fixed Version runtime (optional)
If choosing Fixed Version instead of Evergreen, the Fixed Version binaries must be packaged with the app and the environment configured before Source is set. For WinForms, this is done via CoreWebView2CreationProperties and BrowserExecutableFolder or via CoreWebView2Environment.CreateAsync in EnsureCoreWebView2Async.

Once the installer is updated to deploy Microsoft.Web.WebView2.*.dll and the appropriate WebView2Loader.dll files with the application, the "system cannot find the file specified" error should be resolved.

References:

Answer 4

Hello @Hal Roenick ,

Thanks for your question.

When you use a setup tool to create an installer, it sometimes forgets to pack all the necessary files. Your installer successfully packed the helper file (WebView2Loader.dll), but it left behind the main control files: Microsoft.Web.WebView2.WinForms.dll and Microsoft.Web.WebView2.Core.dll.

Because these two main files are not sitting next to your .exe inside your main folder (C:\Program Files (x86)\VCAMM Software\Golf League Pro), the app crashes when it tries to open the screen.

You can refer to these following steps:

Open your setup project in Visual Studio.
Open your Application Folder view.
Choose Add -> File...
Go to your main application's bin\Release folder (or bin\Debug, wherever you last built the app).
Select Microsoft.Web.WebView2.WinForms.dll and Microsoft.Web.WebView2.Core.dll and add them to the setup.
Rebuild your installer and try again.

Note: In your main VB.NET project, look at your References (or Dependencies list). Right-click Microsoft.Web.WebView2, select Properties, and make sure the setting called Copy Local is set to True.

I hope this addresses your question. If this response was helpful, please consider following the guidance to provide feedback.