When dealing with Microsoft Virtual Server, there might be situations in which you would need to pass CTRL+ALT+DELETE to the underlying VM.
However, pressing them do not work within a virtual machine because of the interaction between the host operating system and the guest operating system and you will be taken to the output related to the host machine.
To get over this and other special keys, you can use the Remote control menu of the VMRC ( Virtual Machine Remote Control ) as shown in the image below :
As simple as a mouse click 🙂