I just had this same problem here too. We have four other virtual servers,
and this is the first we had a problem with. It is also the only one which is
64-bit, so perhaps that's related. Here's what I did:

1. Go to \Program Files\Microsoft Virtual
Server\WebSite\VirtualServer\activex.
2. Extract the contents of the VMRCActiveXClient.cab to a temporary location.
3. Right click on the VMRCActiveXClient.dll or the VMRCActiveXClient64.dll
file depending if your system is 64-bit or not.
4. Click "open with", browse to /WINDOWS/system32, and open with REGSVR32 to
register the DLL.

You should be able to access VMRC through IE (at least I did). If it works,
delete the files at the temporary location from step 2, and you should be
good to go.

Hope this s!

Steve