Set external sharing on site collections in Office 365

You can control external sharing settings on a SharePoint site collection in Office 365, allowing external users (users who don't have an organization account in your Office 365 subscription) access to your site collection.

Applies to: add-ins for SharePoint | SharePoint Online | Office 365

The Core.ExternalSharing code sample shows you how to control your external sharing settings on a SharePoint site collection. Use this solution to:

• Control external sharing settings during your site provisioning process.

• Prepare your site collection for sharing with external users.

Before you begin

To get started, download the Core.ExternalSharing sample add-in from the Office 365 Developer patterns and practices project on GitHub.

Using the Core.ExternalSharing app

Verify that your Office 365 subscription allows external sharing. To do this:

1. Open your Office 365 admin center.

2. On the left navigation menu, choose SharePoint.

3. On the left navigation menu, choose Sharing.

4. In Sharing outside your organization, ensure that Allow users to invite and share with authenticated external users is On.

Verify your external site settings on your SharePoint site collection. To do this:

1. Open your Office 365 admin center.

2. On the left navigation menu, choose SharePoint to open your SharePoint admin center.

3. In the Site Collection List, select the check box next to the site collection URL that you want to verify your external sharing settings on.

4. On the ribbon, choose Sharing.

5. Review your external sharing settings in the sharing dialog. After running the code sample, return to the sharing dialog to verify that your external sharing settings changed.

When you run this code sample, Main in Program.cs performs the following tasks:

• Gets the SharePoint admin center URL.

• Gets the site collection URL to configure external sharing settings on.

• Gets your Office 365 administrator credentials.

• Calls GetInputSharing, which prompts the user to choose an external sharing setting ( SharingCapabilities) to apply to the site collection. The external sharing settings choices include:

  • Disabled, which turns off external sharing on the site.

  • ExternalUserAndGuestSharing, which enables external user and guest sharing on the site.

  • ExternalUserSharingOnly, which enables external user sharing only.

• Calls SetSiteSharing.

 static void Main(string[] args)
        {
           
            /* Prompt for your Office 365 admin center URL*/
            Console.WriteLine("Enter your Tenant Admin URL for your Office 365 subscription:");
            string tenantAdminURL = GetSite();

            /* End Program if no Office 365 admin center URL is supplied*/
            if (string.IsNullOrEmpty(tenantAdminURL))
            {
                Console.WriteLine("Hmm, i tried to work on it but you didn't supply your admin tenant url:");
                return;
            }
               
            // Prompt the user for an Office365 site collection 
            Console.WriteLine("Enter your Office 365 Site Collection URL:");
            string siteUrl = GetSite();

            /* Prompt for Credentials */
            Console.WriteLine("Enter Credentials for your Office 365 Site Collection {0}:", siteUrl);

            string userName = GetUserName();
            SecureString pwd = GetPassword();

            /* End program if no credentials are entered */
            if (string.IsNullOrEmpty(userName) || (pwd == null))
            {
                Console.WriteLine("Hmm, i tried to work on it but you didn't supply your credentials:");
                return;
            }

            try 
            {
                SharingCapabilities _sharingSettingToApply = GetInputSharing(siteUrl);
                using (ClientContext cc = new ClientContext(tenantAdminURL))
                { 
                    cc.AuthenticationMode = ClientAuthenticationMode.Default;
                    cc.Credentials = new SharePointOnlineCredentials(userName, pwd);
                    SetSiteSharing(cc, siteUrl, _sharingSettingToApply);
                }
            }
            catch(Exception ex)
            {
                Console.WriteLine("Oops, Mistakes can happen to anyone. An Error occured : {0}", ex.Message);
               
            }

            Console.WriteLine("Hit Enter to exit.");
            Console.Read();

        
        }

SetSiteSharing does the following:

• Uses the Tenant.GetSitePropertiesByUrl to retrieve SiteProperties on your site collection.

• Uses Tenant.SharingCapability to determine whether external sharing is enabled on your Office 365 subscription.

• If sharing is enabled in your Office 365 subscription, sets the SiteProperties.SharingCapability to the external sharing settings the user entered.

public static void SetSiteSharing(ClientContext adminCC, string siteCollectionURl, SharingCapabilities shareSettings)
        {
            var _tenantAdmin = new Tenant(adminCC);
            SiteProperties _siteprops = _tenantAdmin.GetSitePropertiesByUrl(siteCollectionURl, true);
            adminCC.Load(_tenantAdmin);
            adminCC.Load(_siteprops);
            adminCC.ExecuteQuery();

            SharingCapabilities _tenantSharing = _tenantAdmin.SharingCapability;
            var _currentShareSettings = _siteprops.SharingCapability;
            bool _isUpdatable = false;

            if(_tenantSharing == SharingCapabilities.Disabled)
            {
                Console.WriteLine("Sharing is currently disabled in your tenant! I am unable to work on it.");
            }
            else
            {  
                if(shareSettings == SharingCapabilities.Disabled)
                { _isUpdatable = true; }
                else if(shareSettings == SharingCapabilities.ExternalUserSharingOnly)
                {
                    _isUpdatable = true;   
                }
                else if (shareSettings == SharingCapabilities.ExternalUserAndGuestSharing)
                {
                    if (_tenantSharing == SharingCapabilities.ExternalUserAndGuestSharing)
                    {
                        _isUpdatable = true;
                    }
                    else
                    {
                        Console.WriteLine("ExternalUserAndGuestSharing is currently disabled in your tenant! I am unable to work on it.");
                    }
                }
            }
            if (_currentShareSettings != shareSettings && _isUpdatable)
            {
                _siteprops.SharingCapability = shareSettings;
                _siteprops.Update();
                adminCC.ExecuteQuery();
                Console.WriteLine("Set Sharing on site {0} to {1}.", siteCollectionURl, shareSettings);
            }
        }

See also

• Office 365 development patterns and practices solution guidance

• Manage external sharing for your SharePoint Online environment