This is the error message that people sometimes get:

You can see it on that link, so we can illustrate this issue.

This is the steps to solve the problem:

1. got to regedit in sharePoint servers (Search Server) then go to this path
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Shared Tools\Web Server Extensions\14.0\WSS\Services\

and remove the following:

2. And then go to this path and remove this:

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Shared Tools\Web Server Extensions\14.0\WSS\ServiceProxies\

3. Restart the server

Hope it helps