I'm running Windows XP and using Adobe Reader 9.2 with Acrobat 6.0 installed.
In the last couple of weeks Adobe Reader has suddenly stopped opening some PDF documents (but not all) in Firefox 3.5.6.
The error message is attached. "The Adobe/Acrobat Reader that is running cannot be used to view PDF files in a web browser. Please exit Adobe/Acrobat Reader and exit your web browser and try again".
Any ideas what has gone wrong?