"Error: File format not recognizable" in workspace

[Arno Peeters]

PT2019.12 High Sierra

Transferred my SFX-database to another SSD-drive (AFPS formatted) and made a fresh catalog. At first I had quite a bunch of 'file format unknown' in there, so I deleted the Wavecache and Workspace and made an new catalog.
After rebuilding the catalog they are still there and Calculating Waveform Overview takes forever. Upon closer inspection, it says" Error: File format not recognizable - 'comm' chunk(s) missing", but the files play fine in QuickTime.
It's with AIFF, WAV and MP3 and from different libraries. So no specific kinds of files.
Any ideas?

[Arno Peeters]

I guess I cracked it: it's only with AIFC-files. The 'unknown' WAV files turned out to be aliases left from rooting out duplicates and the few MP3 files were (indeed) corrupt.
Also dragging or importing does not work...
But the Wiki still states:

Pro Tools handles WAV, AIFF, AIFC, mp3, and formerly SDII audio files.

??!