courier-imapis used as Horde backend.
Login to Horde with correct username and wrong password fails with the following confusing error message:
A fatal error has occurred
Call to a member function write() on a non-object
Details have been logged for the administrator.
/var/log/psa-horde/psa-horde.logcontain this error message:
EMERG: HORDE [imp] Call to a member function write() on a non-object [pid 8942 on line 4428 of "/usr/share/psa-pear/pear/php/Horde/Imap/Client/Socket.php"]
This product issue is registered with id #PPPM-3081 and it will be fixed in further Plesk updates.
There are several possible workarounds:
Apply the patch :
# wget --output-document=/root/horde.patch http://kb.plesk.com/Attachments/kcs-54634/horde.patch
# patch --backup --verbose --input=/root/horde.patch /usr/share/psa-pear/pear/php/Horde/Imap/Client/Socket.php
usr/share/psa-pear/pear/php/Horde/Imap/Client/Socket.php.orig' backup file will be created during the patching process.