Hyper-V-Integration-Data-Exchange Error (ID 4096)

Hello,

while I am doing Backups (DPM2012) of my virtual machines, I see the following error:
'VMNAME': The Data Exchange integration service is either not enabled, not running or not initialized. (Virtual machine ID 2C69E8FF-32C2-4489-BE06-FEFFD2DA4C13)

The command get-vmintegrationservices of the VM shows:
VMName      Name                    Enabled PrimaryStatusDescription
VMNAME      Time Synchronization    True    OK                                                
VMNAME      Heartbeat               True    OK                       OK                        
VMNAME      Key-Value Pair Exchange True    OK                                                
VMNAME      Shutdown                True    OK                                                
VMNAME      VSS                     True    No Contact                                        
VMNAME      Guest Service Interface False   OK        

All needed Services are up and running.
When I check the VSS Writers in the VM there are all Writers in stable state with no error

Hyper-V Host is running on Windows Server 2012 R2
Integration Services are up to date (6.3.9600.16384)
VM is Running Windows Server 2008 R2

The backup with DPM of the VM using Hyper-V online backup is successfull.

Does someone know, what these errors try to tell me?

Thanks.

Greets,

torsten