On a Windows Server 2012 R2 Hyper-V cluster I had an issue whereby backups were failing with VSS errors.

When running VSSAdmin List Writers I received the response: “Waiting for responses. These may be delayed if a shadow copy is being prepared.”

In order to resolve this I restarted the COM+ Event System service.  Following this VSSAdmin List Writers failed to return anything.

When restarting the COM+ Event System service there are a number of dependant services.  I noticed that the COM+ System Application service hadn’t automatically restarted.  I started the service, then restarted the services below.  Following this VSSAdmin List Writers returned the expected list of writers.

• EqualLogic VSS Requestor – Specific to my use of EqualLogic storage
• EqualLogic VSS Service – Specific to my use of EqualLogic storage
• Hyper-V Virtual Machine Management
• Microsoft Software Shadow Copy Provider
• Volume Shadow Copy