First login error

[facedirect]

After I type Username and password, I have error - Login Failed. Help please resolve it :'(
Logs
errors.log
IMAP Error: Login failed for admin@domain.com against imap.timeweb.ru from 159.148.92.178. AUTHENTICATE PLAIN: Authentication failed. in /home/c/cu57001/mailserver/public_html/program/lib/Roundcube/rcube_imap.php on line 211 (POST /?_task=login&_action=login)
imap.log
<555b8d80> [C2CD] Connecting to imap.timeweb.ru:143...
<555b8d80> [C2CD] S: * OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE LITERAL+ STARTTLS AUTH=PLAIN AUTH=LOGIN] Dovecot (Ubuntu) ready.
<555b8d80> [C2CD] C: A0001 AUTHENTICATE PLAIN ****** [45]
<555b8d80> [C2CD] S: A0001 NO [AUTHENTICATIONFAILED] Authentication failed.

[Dmitry42]

Can you connet to your mail server from outlook, apple mail or another mail program ?

Show us your RC config. imap_host and smtp_host variables.