SAP Business One V9.0 PL05 - Screen crashes

Forum,

Since upgrading to V9.0 PL05, we have noticed that SAP has started crashing and failing to refresh the screen(s) / Menus probably.

The machines are Windows 7.

I have set the following setting to no avail:

Go to Control Panel -> System.

Choose the Advanced tab.

Under Performace choose Settings

Select Adjust for Best Perfomance

Hit Apply and OK.

Restart the computer

The screen(s) look like this:

Also when performing general operations on client machines, invoices, orders etc... the following message appears:

They are fairly decent in spec and I cannot understand why this is happening.

Any help or advise would be greatly received as this is becoming increasinly frustrating.

Thanks

Sarah