An active remote client has recently sent requests to this machine

Trying to get Windows 7 to sleep is notoriously difficult. Like many, I was in the situation that I got the following message:

C:\Windows\system32>powercfg /requests
DISPLAY:
None.

SYSTEM:
[DRIVER] \FileSystem\srvnet
An active remote client has recently sent requests to this machine.

AWAYMODE:
None.

Needless to say, the Management Console's fsmgmt.msc was silent about any active sessions, so the message seems to be a lie.

In order to make the message disappear, I ended up creating a homegroup, activating media streaming and waiting for the whole process to finish (there is a message in the control panel while it is still busy »sharing«). Afterwards, I simlpy »left« the homegroup again, and voilá, the srvnet request disappeared.

There is also a setting in the advanced power options about letting the computer sleep while sharing media, but that seems to have no effect either way.