Visual Studio 2017 can't connect to TFS 2017: LoadCachedCredentialsFormRegisterdProviders Method not found
  
 
     
     
             
                 
 
 
         
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 We are using Visual Studio 2017 & TFS 2017 .   I have access to TFS web portal & TFS server (remote, share, db,..) & ... and everything works, but I can't connect with Visual Studio  ( just in my pc ).   Error is:      Server 'http://tfs:8080/tfs' was not added.       Method not found:       'Microsoft.VisualStudio.Services.Common.VssCredentials       Microsoft.VisualStudio.Services.Common.VssCredentials.LoadCachedCredentialsFromRegisteredProviders(System.Uri, Boolean ByRef)'.     Firewall is Off  Antivirus is Disable  Remove All Credentials in Credential Manager  Check port access with telnet  VS Version is 15.5.6  TFS Version is 15.117.26714.0   Any advice?   Screenshot      
 
         
             
                 visual-studio tfs 
             
         
 
     
         
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