We've just completed an upgrade of our 6 DCs from W2K3 R2 to W2K8 SP2 and now DPM 2007 refuses to backup the System States of these DCs. The error is always 'Replica is inconsistent', I've deleted the existing protection group and just re-created with 1 DC - I figure if I can get it working on 1 I can replicate whatever I need to do to make it work!

So far i've tried:

Updating the Agent to 2.0.8844.0 (the latest version I think)

Added the AllowSSBToAnyVolume registry entry (set to 1) to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic es\wbengine\SystemStateBackup on the DC

(I'm still unable to run a backup to a critical volume even after changing this entry)

Changed the following entry in PSDataSourcesConfig.xml
<FilesToProtect>D:\DPM_SYSTEM_STATE\%computername% .bkf</FilesToProtect>

(was %SystemDrive%\DPM_SYSTEM_STATE\%computername%.bks)

I'm now out of ideas, hoping someone else has some! The DPM server runs W2K3 x64 Enterprise.