You run a Distributed Transaction through the Managed Provider for DB2 that's included in Microsoft Host Integration Server 2013. Under certain rare conditions, the Microsoft Distributed Transaction Coordinator (MS DTC) service throws an exception in the Dbgtrace.dll process when you use logical unit Type LU 6.2. In this situation, the service stops running.
Under certain timing conditions, a thread tries to call in to the Dbgtrace.dll file after the file is unloaded. This causes the MS DTC service to stop running.
The fix that resolves this problem is included in the following cumulative updates:
Cumulative Update 3 for Host Integration Server 2013
Cumulative Update 2 for Host Integration Server 2013
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.