I posted about this over 6 months and am still looking for a solution. My photos were mainly annotated using MediaDex before I bought Photo Mechanic so I assume that's where the problem comes from. MediaDex is no more.
I have two versions of metadata that I can see clearly using ExifTool, as well as in the Windows 7 Photo Gallery tag list. The old version does not show up in Photo Mechanic though. In ExifTool it's listed as ApplicationRecordVersion 2 (the old stuff) and ApplicatonRecordVersion 3 (the 'correct' version).
ExifTool will not save the changes if I try to delete it. The old tags show up in Windows 7 Search which is mainly why I'd like to get rid of it, and it clutters up the view in ExifTool.
Is there some way to get rid of it?