"The search request was unable to connect to the Search Service." message when searching

For server farm with seperate index server
1)In CA stop both searches Office SharePoint Server Search Windows SharePoint Services Search
2)On application/index server stop Windows SharePoint Services Timer Service
3) Clear sharepoint cache (directions in another post)
4) Restart Timer Service
5) Start Windows SharePoint Services Search in CA
6) Office SharePoint Server Search

Note: Query and Indexing
Check Use this server for indexing content
Use this server for serving search queries