Error in Volume Shadow Copy Service

Hi

When I make backup of Exchange 2007 Information Stores I get the error:

Backup Final error: 0xe000fed1 A failure occurred querying the Writer status.
I found out that this is related to the VSS service, rebooted the server, 5
times.
Still get the same error. Every time I backup Exchange.

I also tryed:
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H:\>VSSADMIN LIST WRITERS
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001 Microsoft Corp.

Writer name: 'System Writer'
Writer Id: {e8132975-6f93-4464-a53e-1050253ae220}
Writer Instance Id: {f05beafe-8f14-462a-b303-d8d1cd7867bb}
State: [7] Failed
Last error: No error

Writer name: 'Microsoft Exchange Writer'
Writer Id: {76fe1ac4-15f7-4bcd-987e-8e1acb462fb7}
Writer Instance Id: {833f0079-1c4a-4988-8508-4245b8aee089}
State: [7] Failed
Last error: Retryable error
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The server is a Windows 2003 Standard R2 SP2 64x

All windows updates are installed.

Does anyone have a solution to this?

Kind regards

Ruben