One day when I wasn’t thinking, I encountered the following error when trying to execute a FAST Search for SharePoint PowerShell command such as Get-FASTSearchContentCollection.
Get-FASTSearchContentCollection : Failed to communicate with the WCF service.
At line:1 char:32
+ Get-FASTSearchContentCollection <<<<
+ CategoryInfo : OperationStopped: (:) [Get-FASTSearchContentCollection], AdminException
+ FullyQualifiedErrorId : e107: Failed to communicate with the WCF service
Searching on the Internet yields the following KB article. However, this article did not resolve my issue. In fact, the cause was actually a much simpler solution. I realized I was running the PowerShell window with my personal account. Obviously, this account does not have the required permissions needed inside FAST. To correct the issue, I just did Run as Different User (hold down shift while right clicking on the icon), to run PowerShell with my fastuser account. Once I did that, I could execute the commands I needed.