- Plesk for Linux
- All mail messages migrated from a source cPanel server are shown as corrupted on Webmail(Invalid Address and No subject). The following error is seen on
CONFIG_TEXT: dovecot Error: service=imap, email@example.com, ip=[127.0.0.1]. Mailbox INBOX: UID=33261: read(/var/qmail/mailnames/example.com/username/Maildir/cur/1520269963.M402118P28216V0000000000000802I00000000001840FA.CL0016UC-SG1.WEBVIS.NET,S=1448:2,S) failed: Cached message size larger than expected (1448 > 1188, box=INBOX, UID=33261)
dovecot: Error: service=imap, firstname.lastname@example.org, ip=[127.0.0.1]. Corrupted record in index cache file /var/qmail/mailnames/example.com/username/Maildir/dovecot.index.cache: UID 33261: Broken physical size in mailbox INBOX:
- On the source cPanel server, dovecot has compression enabled:
# cat /etc/dovecot/dovecot.conf | grep zlib
zlib_save_level = 6
Plesk migrator transfers messages from cPanel "as-it-is" without any modifications, so the messages are compressed after the migration and Plesk is not able to work with them. This Plesk Migrator extension bug with ID #PMT-4651 which plans to be fixed in future extension updates.
As a workaround, it's necessary to unpack the mail messages on the target Plesk server manually so it will be able to read the messages properly. This task is supposed to be performed by a system administrator. It's recommended to read through the official dovecot documentation.
There are some available solutions online such as the following, but they are not officially tested and supported.