I have 2 email routers set up on separate servers for connecting to CRM Online. This organisation receives a large amount of email that needs to be promoted.
Some emails are not be sent to CRM. The email from the router is this:
12/21/2012 09:49:26 : #9628 - An error occurred while delivering the e-mail message with subject "RE: visit to the storage" in mailbox <emailAddress>for delivery to https://disco.crm4.dynamics.com/<org>. System.ServiceModel.FaultException`1[Microsoft.Xrm.Sdk.OrganizationServiceFault]:
The plug-in execution failed because no Sandbox Worker processes are currently available. Please try again.
System.ServiceModel.CommunicationException: Microsoft Dynamics CRM has experienced an error. Reference number for administrators or support: #53F1276A (Fault Detail is equal to Microsoft.Xrm.Sdk.OrganizationServiceFault).
Has anyone seen this before? I can't see a huge amount on the web relating this to the email router.