Pro-Exchange,Lync & Office 365
Belgian Microsoft Unified Communications Professionals
Microsoft Exchange Server, Microsoft Lync Server & Office 365
IT-Pro chalk talk : Question 1 about Exchange Server Backpressure kicking in

Our latest event “IT-Pro Chalk Talk” co-hosted with Winsec & IT-Talks was very interactive and several questions arose during that session.
This is the first question that I will summarize what we all talked about.

Question : Exchange Backpressure keeps kicking in because of diskspace issues and we don’t really know where to look for

Background : If Exchange Backpressure kicks in then All message flow stops, and the server rejects all new connections and messages. (Hub Transport server)
More information here :

Answer :

Monitor the disk usage on the Exchange Server if possible :

  • Use Performance monitor
  • System Center Operations Manager
  • Other tools …
  • Use alerting to inform disk space usage


If diskspace is already low and you want to find out what folders are very big:





  • Disable backpressure as a last resort
  • Use mount points to use other storage/disks

Posted 03-17-2010 1:00 by Johan Delimon
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