Critical error of Source Control Provider in RH 2017 using TFS 2017

Since updating from TFS 2013 to TFS 2017, RH 2017 has a problem when we Generate (WebHelp) and produces the message "Critical error of Source Control Provider.  Please restart IDE.".   No problem generating help via a PowerShell script that we've been using for years.  A Microsoft blog suggested first removing the output folder but that didn't help.  Any assistance would be greatly appreciated.