Go into your media file folders and move the files to another folder. Try starting your Avid. If Avid starts and the databases rebuild, then you do have file corruption somewhere. Add files back into the Media Folders (usually sort by file creation date – oldest first and 1 month at a time). After adding a month restart your Avid. When you get to the point that the Avid databases won’t rebuild, then you’ve found the range of files causing the problem and you can narrow down from there.