not much information there or in your append
On Windows 7, under virtualbox on a linux host. All of the other discussions on this question relate to OS X.
I have reinstalled photoshop, and tried deleting preferences.
The more information you supply about your situation, the better equipped other community members will be to answer. Consider including the following in your question:
virtualbox on a linux host. does the virtual PC provide any useful information? There an error in your environment you need to find out what the error is.