VMware Workstation 5.5Features | Documentation | Knowledge Base | Discussion Forums
A guest operating system and its applications may react unexpectedly when the Workstation console size is not a standard VESA resolution (e.g. 640×480, 800×600, 1024×768, etc.).
For example, the Autofit Guest and Fit Guest commands allow your guest operating system screen resolution to be set smaller 640×480, and some installers do not run at resolutions smaller than 640×480. Programs may refuse to run. Error messages may include such phrases as "VGA Required To Install" or "You must have VGA to install."
There are two ways to work around this problem with nonstandard resolutions.