Cannot refresh more than one site at the time

Hi there,
I suddenly have a problem refreshing more than one site at a time within the control Center.

If I do mark one site and refresh this, then everything work well.

If I however mark two or more sites and then click "refresh info" it looks like the process is starting "retrieving info", but within a second the process seem to stop, and revert to the "manage websites" screen without any changes done.

any idea?

Perfect, that sorted my problem.
Thanks a lot for a speedy resolution.
Reg.
Goran