Today at a client, we stumbled upon a problem when updating MOSS2007 SP2 with .Net Framework 3.5 SP1. Everything seemed to work fine, but Search & indexing was not working anymore. The error log showed the following: EventID 6482 - Application Server Administration job failed for service instance Microsoft.Office.Server.Search.Administration. SearchServiceInstance
Indexing and serving search queries is handled by diffetent servers in the clients environment.

After a bit of googling and bingging we foud this exelent post by Andera Glaser that decribes the problem and the solution to the problem.

More info about how to fix the problem: