ACDSee Encountered and Error and will Shut Down

[Photogimp]

I am getting this error message consistently when attempting to access photo files from 2005 and back. Newer folders do not seem to be similarly effected.
I can access the files in File Explorer so they do not seem to be corrupted. Any ideas what might be going on?

[GusPanella]

Not sure... could be database related...
I am not sure this will work, but maybe try
Database > Optimize Database... make sure to select both "optimize database and tables" and "remove orphans from database"

[Emil]

The fact, that this only affects old photos arouse my curiosity. Could you upload one of them unchanged to a file hoster and post a link please. I've seen this failure many times, but never noticed that it affected old images only.

Though Gus' tip is good, here's another one: Embed all meta data into the images files, create a new database and cataloge all files again. Both tips are standard procedures and described in this forum many times. But both procedures also may not result in a AC performing better. There's other defects that lead to the same error message. Some times it's even a combination of several quirks.