It's happening really something with the mail subsystem there :D since 3.1.3 I get many error of this type: ERROR: OTRS-otrs.PostMasterMailbox.pl-10 Perl: 5.10.1 OS: linux Time: Wed Apr 11 10:40:02 2012 Message: Found no Queue for DWH-SIT::Install! Traceback (2751): Module: Kernel::System::Queue::QueueLookup (v1.136) Line: 515 Module: Kernel::System::PostMaster::DestQueue::GetTrustedQueueID (v1.27) Line: 118 Module: Kernel::System::PostMaster::Run (v1.87) Line: 354 Module: Kernel::System::MailAccount::POP3::Fetch (v1.9) Line: 201 Module: Kernel::System::MailAccount::MailAccountFetch (v1.17) Line: 424 Module: main::Fetch (v1.4) Line: 180 Module: /opt/otrs/bin/otrs.PostMasterMailbox.pl (v1.4) Line: 93 But, beleve me, the queue is live. it's become keysensitive something ? I admit that the filter and the real name doesn't match for this reason... but it was as is since 3 year up to now ;)