Had issues when configuring FAST on SharePoint 2010, specifically with resolving unexpected errors occurred while communicating with Administration Service. Needed to configure FAST Search Keywords.

But, visiting Site Settings for the FAST Search Centre and clicking FAST Search keywords displayed this:

Unexpected error occurred while communicating with Administration Service.

Trying to access Fast Search site promotion and demotion and Fast Search user context also displayed the same error. Took a look at the FAST Connector back in Central Admin, and went into the FAST Query Search Service Application here:

Tried using all options on this page, managed properties, crawled property categories, manage property extraction and spell checking management and each displayed the exact same error.

Examining the ULS logs did not reap many rewards either, no state of a failure just entries stating that the request page for the relevant option was opened, then closed.

Checked the permissions and the web application account was in the relevant FAST Search groups, no issues there…

Then decided to look closer at the FAST Search Server itself via IIS, and noticed that the FASTSearchAdminServices and the ResourceStore web sites were both in Stop state. Attempted to start them resulted in a dialog stating that WAS and World Wide Web Publishing services were not started. Therefore, opened up Services and started WAS and WWW Publishing services, then started the two web sites.

Went back to the relevant options and retried them to find that all of them were functional!

Therefore, to resolve:

1: Check the permissions are correct – ensure the application pool of the relevant web applications are members of the FASTSearchAdministrators group.

2: Ensure that Windows Process Activation Service and World Wide Web Publishing Service are started

3: Ensure that in IIS the Websites FASTSearchAdminServices and ResourceStore are started

Final Note.

How did those sites end up in a stopped state? Well, it’s possible that these sites ended up in a stop state after a reboot. Additionally, there have been known instances where IIS was never provisioned properly as part of the FAST install, meaning that one would have to deploy the relevant services and features; then start up the services as pointed above.

Hope this helps!