IMAP Account Failing

[nltui]

OTRS version: 5.0.17-01
CentOS Linux release 7.3.1611 (Core)

I'm having a strange problem with an account I'm using for OTRS. I don't have any clue if this problem is being caused by OTRS or if it's an Exchange issue. The account for our help desk just stopped working. All of the sudden it can't authenticate to our organizations Exchange server. This happened a month ago and we had to delete the old account and create a new one.

The message I get is, "Message: IMAPS: Auth for user myuser@ad.mywork.edu/imap.mywork.edu failed!"

There are 4 other accounts configured on that server that don't have any problems, but they don't have anywhere the traffic that this one does.

The error from messages:
Apr 11 13:55:10 tickets OTRS-otrs.Console.pl-Maint::PostMaster::MailAccountFetch-0[4079]: [Error][Kernel::System::MailAccount::IMAP::_Fetch][Line:142]: IMAPS: Auth for user myuser@ad.mywork.edu/imap.mywork.edu failed!
Apr 11 13:55:13 tickets OTRS-otrs.Console.pl-Maint::PostMaster::MailAccountFetch-0[4079]: [Error][Kernel::System::Daemon::DaemonModules::BaseTaskWorker::_HandleError][Line:51]: There was an error executing Execute() in Kernel::System::Console::Command::Maint::PostMaster::MailAccountFetch: ERROR: OTRS-otrs.Console.pl-Maint::PostMaster::MailAccountFetch-0 Perl: 5.16.3 OS: linux Time: Tue Apr 11 13:55:10 2017#012#012 Message: IMAPS: Auth for user myuser@ad.mywork.edu/imap.mywork.edu failed!#012#012 Traceback (4079): #012 Module: Kernel::System::MailAccount::IMAP::_Fetch Line: 142#012 Module: Kernel::System::MailAccount::IMAP::Fetch Line: 86#012 Module: Kernel::System::MailAccount::MailAccountFetch Line: 440#012 Module: Kernel::System::Console::Command::Maint::PostMaster::MailAccountFetch::Run Line: 94#012 Module: (eval) Line: 460#012 Module: Kernel::System::Console::BaseCommand::Execute Line: 454#012 Module: (eval) Line: 150#012 Module: Kernel::System::Daemon::DaemonModules::SchedulerTaskWorker::Cron::Run Line: 129#012 Module: Kernel::System::Daemon::DaemonModules::SchedulerTaskWorker::Run Line: 250#012 Module: (eval) Line: 316#012 Module: main::Start Line: 316#012 Module: bin/otrs.Daemon.pl Line: 138

[nltui]

This is an Exchange issue. Exchange was reaching it's MAPI limit, because people had the mailbox mounted in Outlook, and MAPI will create several connections per session. Exchange will favor MAPI connections over all other connections, thus it was locking out the OTRS IMAP connection.