Firstly, just make sure that your email polling logic is not simply hammering Outlook/Mapiex continually without any delays between attempts. This would probably cause an issue with any application and will also probably fill your database session log table very quickly. You probably already have, but I recommend a sleep of between 10 and 30 seconds after no emails are found before the next polling attempt.
Secondly, listenter errors showing on the resource suggest a network issue to me. That could be caused if you are hammering the database with constant polling and logging turned on - so do my first suggestion and also turn off logging. If not that then you need to look into what other network issues there may be in your environment?
Lastly, how do you put newlines into responses in this new forum? I have tried syntax but it does not work?