I created an empty test in ACT that simply does this

Test.SendRequest("http://localhost")

When I try to run it, I get:

Connecting to the test clients...
Could not bind to Windows Management on a test client.
Test client 'PC15452' did not start. Error value: 0x80041003
Waiting for the test clients to start...
The test is no longer running.

Does anyone know what this could be?

Thanks!

I found the solution in KB 328217 article:

http://support.microsoft.com/default.aspx?scid=kb;en-us;328217