SymptomsAfter upgrading of Parallels Plesk Panel to version 9.0 IMAP/POP3 authorization does not work.
CauseIt is incorrect upgrading procedure for mail packages that causes the problem. The procedure is under investigation now and will be fixed in future patch for Parallels Plesk Panel version 9.0.
ResolutionTo fix the problem you should reconfigure mail with utility mchk or mailsrv_entities_dump.
~# PRODUCT_ROOT_D/admin/sbin/mchk --help
Run mchk with needed parameters.
Additional informationUse the following articles to get values of PRODUCT_ROOT_D and PLESK_LIBEXEC_DIR for your system: