Corrupt User Database?

My mailinabox instance now cannot send emails.

Trying from the web interface or IMAP the mail.log shows:

Jan 1 15:53:57 box postfix/trivial-rewrite[11360]: fatal: dict_sqlite_lookup: /etc/postfix/ SQL p
/O error?
Jan 1 15:53:58 box postfix/submission/smtpd[11361]: connect from unknown[REDACTED IPV6]
Jan 1 15:53:58 box postfix/submission/smtpd[11264]: warning: problem talking to service rewrite: Application error
Jan 1 15:53:58 box postfix/master[8926]: warning: process /usr/lib/postfix/sbin/trivial-rewrite pid 11360 exit status 1
Jan 1 15:53:58 box postfix/master[8926]: warning: /usr/lib/postfix/sbin/trivial-rewrite: bad command startup – throttl

and mail.err:
Jan 1 15:49:42 box postfix/trivial-rewrite[6392]: fatal: dict_sqlite_lookup: /etc/postfix/ SQL pr
O error?

All I did today was change a users password for them.

Am I able to restore just the user database or should I restore a full backup from a day ago?
Am I even right about the failure?

All lights are green on the dashboard. All system updates installed and the box has been rebooted.

Thanks in advance!

So I have fixed it for now following this advice:

cd /home/user-data/mail
sudo sqlite3 users.sqlite ‘PRAGMA journal_mode=delete;’;

from this thread:

So I am back in action and I also now know how it happened.
One of my users asked me the day before “I tried to change my password but it failed” and I think that was when mail sending stopped working.

Seems a pretty big issue!

Now I have stopped panicking I can see it’s a well documented problem seen by a few and even fixed in v60.4

I will tell my users to avoid trying to alter passwords themselves until that lands!

sudo sqlite3 users.sqlite ‘PRAGMA journal_mode=delete;’; - can give you an error with database is locked (5)

the solution I found to keeps those changes from all the passwords and users is backing up the users.sqilte file and run the sqlite3 command (above). This is what I did

cp /home/user-data/mail/users.sqlite /home/user-data/mail/users.sqlite.bk
sudo sqlite3 users.sqlite.bk ‘PRAGMA journal_mode=delete;’;
cp /home/user-data/mail/users.sqlite.bk /home/user-data/mail/users.sqlite

cd /home/user-data/mail
cp /home/user-data/mail/users.sqlite /home/user-data/mail/users.sqlite.bk
sudo sqlite3 users.sqlite.bk ‘PRAGMA journal_mode=delete;’;
cp /home/user-data/mail/users.sqlite.bk /home/user-data/mail/users.sqlite