Du: cannot access '/var/mail/...,Sb': Bad message

Unfortunately not ;-( it happened again. I can no more backup the system part of Yunohost. And now I also have it there :

/etc/cron.daily/dpkg:
mv: failed to access './/dpkg.status.0': Bad message
touch: cannot touch './/dpkg.status.0': Bad message

It looks like corrupted files that come again and again but I don’t know why. Even if I fix the files, it will happen again in a few weeks. Last time I tried to run fsck I could not even start anymore and I had to reinstall everything from scratch.

I can’t figure out what happens. I’m not a Debian expert I now think about giving up self-hosting. I really like Yunohost but I can’t spend my time restoring the system periodically.