AD User executing agent job needs to have SQLAgeUserRole in msdb and be owner of job.
https://technet.microsoft.com/en-US/library/ms188283(v=SQL.110).aspx
Month: August 2015
Unable to begin distributed transaction
Symptom: The transaction manager has disabled its support for remote/network transactions
Issue: Need to enable inbound/outbound transaction manager communication
Solution:
1. Open Component Services Snap-in (dcomcnfg)
2. Browse to Console->Component Services->Computers->My Computer->Distributed Transaction Coordinator
3. Right Click Local DTC and select properties
4. Select Securty tab
5. Check Network OTC Access, Check Allow Inbound, Check Allow Outbound
6. Click OK
7. DTC services should restart and then can give it a test
Additional info:
http://sysadminwebsite.wordpress.com/2012/05/29/9/
http://msdn.microsoft.com/en-us/library/aa561924.aspx