The Exchange support team relatively frequently receives cases where mobile devices using Exchange ActiveSync (EAS) protocol send too many requests to Exchange server resulting in a situation where server runs out of resources, effectively causing a ‘denial of service’ (DOS) attack. The worst outcome of such a situation is that the server also becomes unavailable to other users who may not be using EAS protocol to connect. We have documented this issue with possible mitigations in the following KnowledgeBase article:

Read the complete blog and download the script at http://blogs.technet.com/b/exchange/archive/2012/01/31/a-script-to-troubleshoot-issues-with-exchange-activesync.aspx

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