No Sorting Configuration in the Search Action Links Web Part

I recently ran into an issue where none of the sortable managed properties were appearing in the Sorting Configuration Section of the Search Action Links web part. Normally, you would expect to see something like this…

…except with additional sort fields. Relevance and ProcessingTime were all that I could get to appear. This was part of a SharePoint 2010/FAST Search installation that was otherwise behaving as expected. Search results were appearing, refiners were refining, and everything seemed fine with the exception of a mysterious lack of sort options. A quick check of the log reveled the following error:

Could not retrieve Sortable Fields from FAST AdminOM(SchemaOM)! Microsoft.SharePoint.Search.Extended.Administration.Common.AdminException: Failed to communicate with the WCF service. ---> System.ServiceModel.Security.SecurityAccessDeniedException: Access is denied.    Server stack trace:      at System.ServiceModel.Channels.ServiceChannel.ThrowIfFaultUnderstood(Message reply, MessageFault fault, String action, MessageVersion version, FaultConverter faultConverter)     at System.ServiceModel.Channels.ServiceChannel.HandleReply(ProxyOperationRuntime operation, ProxyRpc& rpc)     at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout)     at System.ServiceModel.Channels.ServiceChannelPro...           

Based on the suggestion from a co-worker (Andrew Crowder), that the user making the call might not be part of the FASTSearchAdministrators group, I decided to compare the group membership against all the Application Pool service accounts. It turns out the account being used for the Search Admin Service Web Pool was not present in the group. You can check for the identity of this account on the properties for the FAST Content SSA:

Simply adding the indicated account into the FASTSearchAdministraotrs group fixed the problem. Yet another case where closely following the FAST installation instructions would have prevented problems.