Incoming Email Service Job Lock Type Change between SharePoint 2010 and 2013

EDIT: 12/12/2013: The LockJobType in SharePoint 2013 has been changed back to None in the December 2013 CU (http://support.microsoft.com/kb/2837677/en-us), allowing the SharePoint Administrator to run the Incoming Email Service on more than one server!

In SharePoint 2010, the Incoming Email service timer job had an SPJobLockType of None, which means that the job ran on all servers in the farm, given the Incoming Email service was provisioned.

In SharePoint 2013, that SPJobLockType has changed to Job, which means it only runs on a single member in the farm. This is a problem for those who wish to use round-robin MX records. While in SharePoint 2010, you could have multiple SharePoint servers, using equally weighted MX records servicing Incoming Email requests, in 2013, you can only have a single server servicing Incoming Email requests. Disable the Incoming Email service on all SharePoint 2013 servers except the one designated by the MX record. This will prevent the Incoming Email service timer job from running on a server which does not contain any email to be picked up.

SharePoint 2010:

public SPIncomingEmailJobDefinition(string name, SPService service) : base(name, service, null, SPJobLockType.None)
{
}

SharePoint 2013:

public SPIncomingEmailJobDefinition(string name, SPService service) : base(name, service, null, SPJobLockType.Job)
{
}

MSDN Reference: SPJobLockType enumeration

Trevor Seward is a Microsoft Office Apps and Services MVP who specializes in SharePoint Server administration, hybrid scenarios, and SharePoint Online. He has been working with SharePoint for 16 years from SharePoint 2003 on up, managing environments with terabytes of content for 150,000+ user organizations. Trevor is an author of Deploying SharePoint 2016 and Deploying SharePoint 2019. You can find him on Twitter and in /r/sharepoint.