I have a Dell Inspiron 530, and I'm having a problem with keeping virtualization enabled. It disables itself after resuming from stand by. The only way to re-enable it is to do a cold boot. There is no option in the BIOS for Trusted Execution. I read other discussions where disabling that resolved the issue, but that isn't in this system's BIOS.
Trusted execution is not required for Windows 7 Virtual PC. Some people are lucky in that setting it resolves the resume problem, but it doesn't solve the problem for everybody and it didn't for me. I had to get a new bios from ASUS. If you aren't using the latest bios from Dell, you should try the latest. If you are using the latest, then you need to report the problem to Dell and see if they will create a new bios.
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