Originally Posted by NJBlackBerry
Locate and delete VENDOR.XML on your C: drive
Sorry for the belated reply, been too busy here lately! But thanks, NJ. Didn't do exactly what you suggested, but you pointed me in the right direction to solve the problem. Finding vendor.xml reminded me that there are TWO separate application directory trees that need to be transferred for it to work successfully. I had transferred C:/Program Files/Research in Motion/Blackberry (where all the Desktop Manager stuff is at) but had forgotten about C:/Program Files/Common Files/Research in Motion (where all the device software is at.)
Transferred both directory trees, and now its working again. Only have one issue now - Desktop Manager doesn't seem to know that there are any third party apps installed, all of which I installed from Desktop Manager in the past. Any way to fix that?