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I upped the Video Memory to 128MB but it did not correct the problem. It wont let me make it any higher than that. If I click on the option that says "install guest additions" I dont really see it doing anything. What should one see happen?

The problem still appears to be the VM session. I am wondering if some iMac setting for the entire machine may coorect this.

Any ideas is appreciated.

Do you see something if you boot in safe mode? (spam F8 when you start VM and select safe mode)

To add to what PerryG said, I just installed Windows 7 on a new 27" iMac. I had the video memory set to 128MB however, the screen would flash between the desktop and the Windows startup screen when I would move windows around the desktop. I increased the video memory to 256MB and all the display issues went away. I assume 128MB video memory is just not enough for the 27" 2560x1440 resolution.

I never did have a black screen and I didn't install the guest additions in safe mode. I'm using the WDDM driver. One thing to check perhaps is to make sure both 3D and 2D are checked in the video settings.

I upped video memory to 256MB and checked the 2d and 3d options but this did not correct the problem. Booting in safe mode gives the same results. After the Windows 7 screen with the colors swirling it goes to a blank screen.

Mickster wrote:I upped video memory to 256MB and checked the 2d and 3d options but this did not correct the problem. Booting in safe mode gives the same results. After the Windows 7 screen with the colors swirling it goes to a blank screen.

I have read that if Windows 7 wasn't activated on install, or wasn't a legal copy, or was previously installed on a different machine you might get the black screen after the boot screen. I was curious about something you had said though. You said this was installed on a new iMac but is running 10.7.5. Apple hasn't sold a Mac with 10.7 since 7/12 that I'm aware of so I assume by new you mean less than a year old.

Yes by new I mean less than a year old iMac. Windows 7 is activated with a valid license.

Is it possible for you to install new win 7 guest and see if the problem persists with this new installation also. ?
Secondly, is booting in safe mode displays the desktop properly or also facing black screen even in safe mode.
Third thing you can try is to uninstall guest additions in safe mode and then try rebooting in normal mode.

Please, let us know the results.

Anshul Makkar

Booting in safe mode produces the same results. It shows all the files being loaded across a black screen with white text but the screen turns black at the point when you would expect to see the Windows desktop.

I resolved the problem by setting up a new virtual machine. I was able to point the new VM to the Windows 7 files from the previously installation and everything is working now. I asked the end user to let me know if the display goes blank again but as of now everything is working.

Mickster wrote:I resolved the problem by setting up a new virtual machine

In that case it was a VM configuration issue, since if you keep the same disk then that is the only possible difference. Right now I assume you're using defaults from the Win7 template. Might be worth digging to pinpoint the important change.

I solved this problem by disabling 3D acceleration.