The issue:
In SharePoint 2013 on a Windows Server 2012 R2 web server, when trying to add a domain user to a group or permissions, you receive the following message, “Sorry, we’re having trouble reaching the server.” You may have noticed this when trying to add users as farm administrators.
Possible causes:
1: The server does not have enough resources to process the function without timing out. Verify you have the resources below (Source: http://technet.microsoft.com/en-us/library/cc262485.aspx).
| Installation Scenario | Deployment type and scale | RAM | Processor | Hard disk space |
|---|---|---|---|---|
| Single server with a built-in database or single server that uses SQL Server | Development or evaluation installation of SharePoint Server 2013 or SharePoint Foundation 2013 with the minimum recommended services for development environments. For information, see Minimum recommended services for development environments. | 8 GB | 64-bit, 4 cores | 80 GB for system drive |
| Single server with a built-in database or single server that uses SQL Server | Development or evaluation installation of SharePoint Server 2013 or SharePoint Foundation 2013 running Visual Studio 2012 and the minimum recommended services for development environments. For information, see Minimum recommended services for development environments. | 10 GB | 64-bit, 4 cores | 80 GB for system drive |
| Single server with a built-in database or single server that uses SQL Server | Development or evaluation installation of SharePoint Server 2013 running all available services. | 24 GB | 64-bit, 4 cores | 80 GB for system drive |
| Web server or application server in a three-tier farm | Pilot, user acceptance test, or production deployment of SharePoint Server 2013 or SharePoint Foundation 2013. | 12 GB | 64-bit, 4 cores | 80 GB for system drive |
2: If you are sure you have these minimum resources, which you probably do, it’s time to check HTTP Activation on the web server.
On the server manager page (see below) “Add Roles and Features” and click through to the “Features” tab/page. Make sure under .NET Framework 4.5 Features -> WCF Services that “HTTP Activation” is checked. Under .NET Framework 3.5 Features, make sure HTTP Activation is checked. Click “Next” and Install. You may have to specify an alternate source if these were not already checked. Follow the instructions on the window and you should be fine.
After installing these, you shouldn’t have to restart the web server to see if the changes fixed the issue. Try adding a user again and if it is not fixed, try the next steps.
3: Permissions
Make sure the domain account you are using for a SharePoint service account has the necessary permissions to read domain accounts.
If this didn’t resolve your issue, please let us know. We would be interested to know what your issue was and what the solution was.