Virtual Server 2005 includes a standalone VMRC (Virtual Machine Remote Control) client application - that many people like to use to control virtual machines in demonstration and training environments (where you do not want the end user to have the full UI for configuration and creation of virtual machines).  However one common complaint is that VMRC will display informative pop-up messages about the level of security that is present on the VMRC connection (to let you know when potentially confidential data may be about to be sent in a lower security method than expected).  While this is normally a good thing - it is very distracting for demonstration and training scenarios.

You can disable these pop-up warnings through the following registry values under the key “HKEY_CURRENT_USER\Software\Microsoft\VMRCClient\VMRCServers\server\Policies” where server is the name of the server. (This is the name you typed on the command-line or URL.)

“Allow NTLM Authentication” (DWORD): Set this to 1 to disable the NTLM warning.
“Allow Unencrypted Connections” (DWORD): Set this to 1 to disable unencrypted connection warnings.

This must be done on the machine running the VMRC client and on a per-user basis.

Cheers,
Ben