Plugin Registration Tool - Unable to register new assembly with trial account paid version.

Hi @VIVEK KUMAR

Thank you for reaching out. 

Based on my research, this issue may be related to blocked DLL files within the Plugin Registration Tool (PRT) installation folder. There is a community-reported case where clicking Register New Assembly did not open the file selection dialog, and the issue was resolved after unblocking the PRT DLLs. You can refer via: Solved: Cant register an assembly - Plugin Registration Tool 

You could try to navigate to the PRT installation folder > Tools. Right-click each DLL file, select Properties, and check whether an Unblock option is available. If so, select it and apply the changes. 

Alternatively, you can unblock all files in the PRT folder using PowerShell: 

Get-ChildItem -Path "C:\path\to\PluginRegistrationTool" -Recurse | Unblock-File  

After that, you could try restart the Plugin Registration Tool and test whether the Register New Assembly dialog appears correctly. 

Please note that this summary is based on my own findings and may not fully address your concerns. Since my current category primarily focuses on Office 365 products, and your concern relates to Microsoft Power Apps, I want to ensure you receive the most accurate and effective assistance. For this reason, I recommend posting your question in the Power Platform community. You can post it in both the Power Apps and Power Automate forums to gain insights from both areas of the Power Platform.   

By posting there, you’ll connect with a highly knowledgeable group of contributors who can either share their expertise or learn alongside your scenario, increasing the chances of a quick and relevant solution.  

I apologize for redirecting you to a different community. However, members in this category primarily focus on Office 365 related topics and may have limited experience with Power Platform tools. Guiding you to the appropriate forum ensures you receive faster and more accurate assistance.  

As community moderator, I also sincerely appreciate your understanding that my access to internal development information is limited. My role is to help guide users toward the most suitable resources and support channels. While I may not have visibility into deeper backend analysis, I remain committed to supporting you as best as we can within our scope.  

If you have any additional concerns, feel free to comment below. I would be more than happy to assist.  

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