tasks error

[ladas at seznam.cz]

Hi everybody.

Can someone help, how to repair task internal error? At web GUI I switch in tasks and get ERRORTITLE: server error! (internal server error) and at log file I found:

/var/log/roundcubemail/errors.log:

[12-Oct-2020 20:56:05 Europe/Prague] PHP Fatal error:  Uncaught exception 'Exception' with message 'DateTimeZone::__construct(): Unknown or bad timezone (Z)' in /usr/share/r
oundcubemail/plugins/libkolab/lib/kolab_storage_cache.php:905 
Stack trace: 
#0 /usr/share/roundcubemail/plugins/libkolab/lib/kolab_storage_cache.php(905): DateTimeZone->__construct('Z') 
#1 /usr/share/roundcubemail/plugins/libkolab/lib/kolab_storage_cache.php(636): kolab_storage_cache->_unserialize(Array) 
#2 /usr/share/roundcubemail/plugins/libkolab/lib/kolab_storage_folder.php(301): kolab_storage_cache->select(Array, false, true) 
#3 /usr/share/roundcubemail/plugins/tasklist/drivers/kolab/tasklist_kolab_driver.php(590): kolab_storage_folder->select(Array, true) 
#4 /usr/share/roundcubemail/plugins/tasklist/tasklist.php(1081): tasklist_kolab_driver->count_tasks('VGFza3M') 
#5 [internal function]: tasklist->fetch_counts() 
#6 /usr/share/roundcubemail/program/lib/Roundcube/rcube_plugin_api.php(522): call_user_func(Array) 
#7 /usr/share/roundcubemail/index.php(298): rcube_plugin_api->exec_action('tasks. in /usr/share/roundcubemail/plugins/libkolab/lib/kolab_storage_cache.php on line 905

and sync with android failed too. All new tasks from android are removed, but I can see them in web GUI.


Thank you very much for any advice.

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