Several customers have a common problem with a corrupted email xml state file when an exchange server crashes or is taken offline without stopping the email router. Thanks to my good friend, and MVP Co-worker, Donna Edwards, you can add the following node to process a certain amount of days!

Steps to Restore Service

1. RDP to the CRMServer.
2. Browse to C:\Program Files\Microsoft CRM Email\Service
3. Rename the xml file ‘Microsoft.Crm.Tools.EmailAgent.SystemState.xml’
4. Make a copy of the file ‘Microsoft.Crm.Tools.EmailAgent.xml’
5.  Open the file ‘Microsoft.Crm.Tools.EmailAgent.xml’ in notepad
6.  Add the node  ‘<MessageProcessingThresholdDays>1</MessageProcessingThresholdDays>’ inside the <ProviderOverrides> </ProviderOverrides> tags
   1. The number value represents the number of days from ‘Today (Now)’ to process emails from each mailbox
   2. For example, if you use the number ‘1’ the router will process emails created in the last day
   3. Restart the email router service