For one of my Premier 'FAST search for SharePoint 2010' customers, 'get-FASTSearchSettingGroup' command was throwing an error.
Here are details of the issue and it’s resolution:
When running PowerShell command : "Get-FASTSearchSettingGroup" in order to update a bestbets file, getting an error: "Failed to communicate with the WCF service."
FAST administration app pool account's password was changed so it had to be updated manually in the App pool identity.
· We went to IIS manager and found that the Fast Administration app pool was stopped.
· We manually started it.
· Then went to FAST PowerShell again and ran the command get-FASTSearchSettingGroup which returned the same error.
· Checked that the FAST administration site App pool got stopped again.
· We suspected that the app pool identity was not updated when the password might have been changed for the account.
· Went to app pool and updated App pool credentials with new password.
· Then ran the same PowerShell command and it worked this time.
I Hope that helps! Happy searching !!