Unable to syncronize a mailbox or send an email on Plesk server: Mail handler 'check-quota' said: 452:4.2.2 Mailbox full

Symptoms

• After sending message to mail box john_doe@alias.com the following warning is shown in webmail:

  Roundcube:

  CONFIG_TEXT: An error occurred while saving sent message. Unable to perform operation. No free disk space.

  Horde:

  CONFIG_TEXT: You exceeded mail quota

  Note: The same can be true for mail forwarding.

• The mailbox quota is set to Unlimited or its limit is not reached at Plesk > Domains > example.com > Email Addresses.

• Subscription disk space is set to unlimited or its limit is not reached, which can be seen at Plesk > Domains > example.com > View More Statistic.

• Unable to synchronize a mailbox with a mail client or send an email to john_doe@example.com. The following error appears in /var/log/maillog file:

  CONFIG_TEXT: postfix/pipe[17519]: 7AEB011C1531: to=<john_doe@example.com>, relay=plesk_virtual, delay=25950, delays=25950/0/0/0.12, dsn=4.3.0, status=deferred (temporary failure. Command output: Mail handler 'check-quota' said: REPLY:452:4.2.2 Mailbox full 4.2.1 Message can not be delivered at this time )

  ---

  CONFIG_TEXT: postfix/cleanup[16783]: B22C11DC00BE: milter-reject: END-OF-MESSAGE from smtp.gmail.com[127.0.0.1]: 4.2.2 Mailbox full; from=user@gmail.com to=<john_doe@example.com> proto=ESMTP helo=<smtp.gmail.com>

Cause

The file /var/qmail/mailnames/example.com/john_doe/Maildir/maildirsize is corrupted.

Resolution

1. Connect to the server via SSH.

   Note: if direct SSH access to the server is not possible, contact server administrator for further assistance.

2. Remove the file maildirsize of the affected domain:

   # rm -rf /var/qmail/mailnames/example.com/john_doe/Maildir/maildirsize

   • example.com - a name of an affected domain

   • john_doe - a name of an affected mailbox

3. Recreate the file maildirsize by re-saving the same settings defined in Plesk:

• Log into Plesk.

• Go to Domains > example.com > Email Addresses > john_doe@example.com > click OK without making any changes