dovecot - May 2017 - dovecot log shows: service=imap ... Error: Temp file creation to /tmp/dovecot.imap. failed: No such directory

I am using dovecot 2.2 with plesk 12 and I have made no modifications to the
dovecot config.
Logwatch reports the messages below.
The errors don't seem to appear for every imap connect as can be seen from
the number of deliveries and successful logins.
So what makes dovecot fail sometimes to create the /tmp/dovecot.imap?


Dovecot Deliveries: 19
 Dovecot IMAP and POP3 Successful Logins: 106
 Dovecot disconnects: 72

 **Unmatched Entries**
    dovecot: message repeated 4 times: [ service=imap, user=tester at
example.com, ip=[::1]. Error: Temp file creation to /tmp/dovecot.imap. failed:
No such file or directory]: 1 Time(s)
    dovecot: message repeated 5 times: [ service=imap, user=tester at
example.com, ip=[::1]. Error: Temp file creation to /tmp/dovecot.imap. failed:
No such file or directory]: 1 Time(s)
    dovecot: service=imap, user=tester at example.com, ip=[::1]. Error: Temp
file creation to /tmp/dovecot.imap. failed: No such file or directory: 10
Time(s)
    dovecot: service=imap, user=tester at example.com, ip=[::1]. Error: Temp
file creation to /tmp/dovecot.imap. failed: No such file or directory: 1 Time(s)

On 03.05.2017 08:14, Peter Kielbasiewicz wrote:
> I am using dovecot 2.2 with plesk 12 and I have made no modifications to
the dovecot config.
> Logwatch reports the messages below.
> The errors don't seem to appear for every imap connect as can be seen
from the number of deliveries and successful logins.
> So what makes dovecot fail sometimes to create the /tmp/dovecot.imap?
>
>
> Dovecot Deliveries: 19
>  Dovecot IMAP and POP3 Successful Logins: 106
>  Dovecot disconnects: 72
>
>  **Unmatched Entries**
>     dovecot: message repeated 4 times: [ service=imap, user=tester at
example.com, ip=[::1]. Error: Temp file creation to /tmp/dovecot.imap. failed:
No such file or directory]: 1 Time(s)
>     dovecot: message repeated 5 times: [ service=imap, user=tester at
example.com, ip=[::1]. Error: Temp file creation to /tmp/dovecot.imap. failed:
No such file or directory]: 1 Time(s)
>     dovecot: service=imap, user=tester at example.com, ip=[::1]. Error:
Temp file creation to /tmp/dovecot.imap. failed: No such file or directory: 10
Time(s)
>     dovecot: service=imap, user=tester at example.com, ip=[::1]. Error:
Temp file creation to /tmp/dovecot.imap. failed: No such file or directory: 1
Time(s)
Maybe you are chrooting dovecot yourself? The chroot must contain /tmp
directory.

Aki