ISPConfig 3.2.7p1 User unknown in virtual mailbox table

after update to 3.2.7p1 I'd start having "User unknown in virtual table" just in some accounts. OS was on Debian 9 and also update to 10, but no changes. Don't seem to be a global configuration issue, because some accounts work perfectly. I'm running IspConfig on dozens of servers for years with no issues, so now I'm lost. Any clue ?

 

So upgraded Debian 9 to debian 10? Did you force reconfigure services in ISPConfig after the debian upgrade?
When is this "User unknown in virtual table" error showing up? What is being sent or received? Does the use exist?

 

Easy solution. Go to Tools -> Resync, and in my case, just Mailboxes.

 

Didn't change nothing global. Thank you!

 

Users exist, no quota issues. All mailboxes sent with no problems and just a few account couldn't receive.
What I did was: Tools -> Resync and just check Mailboxes. Problem solved. Thank you !