Coherence Mode is NOT Working

[joehack]

Hello

When try to switch to Parallels Coherence mode under WXP, it shows the following message in a box:

Unable to switch to Coherence Mode. Primary operating system does not support screen resolution requested by guest operating system. Select another resolution for the guest operating system or review your video system configuration.


I am running a MacBook (1st gen) with 2GHz and 2GBytes memory. Attached is a 2nd monitor (17" tft, 1280x1024).
I've already tried all kind of different resultions.

Any ideas?

Thanks for your help!

Regards,
Jochen

[UPDATE]
Unpluggingg the external monitor helps. Any ideas how to work around that?

[M@lew]

Have you checked to see if you're able to use coherence mode with 2 monitors?

[joehack]

@M@lew:
It does not work. At least in my configuration. I think it is caused by the different screen resolutions:
MB: 1280x800
17" tft: 1280x1024

Once the 2nd screen is disconnected, Cohrence works perfectly. :)

It would be interesting to see if Coherence works with two similar screens.

Regards,
Jochen

[kinchee87]

Maybe try increasing the video memory of guest operating system?

[joehack]

I've already tried that. Did not work either.

Jochen

[MacRumorUser]

You have installed Paralells Tools ?

[kinchee87]

Have you checked the option Use multiple displays in Edit ~> Virtual Machine ~>Coherence, under Working area?

[joehack]

Yep, is checked.

[Fjan]

[UPDATE] Unpluggingg the external monitor helps. Any ideas how to work around that?

I had the same error and for me unchecking multiple monitors fixed it. Of course I have two screens and now I cannot use it on my second monitor, but it is better than nothing.

I've already tried increasing video memory. Perhaps the problem is that I have two different sized monitors (24" and 30"). Any other ideas would be welcome.