Windows 2008 (R2) system state fails due to . . .

I have been troubleshooting a issue with a failing System State backup on 2 Windows 2008 R2 servers. These two servers both run Exchange 2010.
The DAG backup with DPM 2010 works perfect, but the system State keeps failing with this error in the application log.
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Log Name:      Application
Source:        Microsoft-Windows-Backup
Date:          2-11-2009 17:36:18
Event ID:      521
Task Category: None
Level:         Error
Keywords:     
User:          SYSTEM
Computer:      <server_name>
Description:
Backup started at '2-11-2009 16:36:13' failed as Volume Shadow copy operation failed for backup volumes with following error code '2155348129'. Please rerun backup once issue is resolved.
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According to some Forum post the error code '2155348129' may be caused by the incorrect Active volume. (When a OEM Partition is the active partition instant of the system partition) 
http://social.technet.microsoft.com/forums/en-US/winserverfiles/thread/d5daada2-b78b-4935-bd9e-80726c26c4a8/ 

But this is not the case here.

A closer look in the application log shows a second error for the Forefront Vss writter:
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Log Name:      Application
Source:        FSCVSSWriter
Date:          2-11-2009 17:36:17
Event ID:      11003
Task Category: (11)
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      <server_name>
Description:
Microsoft Forefront Protection VSS Writer failed when preparing for backup. Writer instance: FSCVSSWriter Error code: 0x00000000
Event Xml:
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Workaround:
I found a workaround With a little help of this post

-> Disable the Forefront Protection VSS Writer in the service Panel

In the same post is also an issue with the SQL VSS\Hyper-V writer mentioned as cause.