Hi found the best way to get a working server back has been to the do the following.
1. Take backup of pubkey.crt and privkey.crt (in Symantec Ghost folder under Program Files)
2. When you attempted an upgrade to 11.5.1 it should have created a backup automatically of thses and stored in the C:\Documents and Settings\All Users\Application Data\Symantec\Version 11.5 Database Backup folder
3. Export your registry HKLM\Software\Symantec\Symantec Ghost\NGServer (32bit) or HKLM\Software\WOW6432Node\Symantec\Symantec Ghost\NGServer (64bit)
4. Uninstall 11.5.1
5. I cleaned up the folders that were left behind (copied them off)
6. Install 11.5.0
7. run ngserver -uninstall
8. Copy DB and .crt files you backed up over the new ones it created.
9. Restore the registry keys you exported
10. Copy any custom drivers over to the new version (and any WinPE PreOS that you may have customised)
11. Run ngserver -install
12. Start Console
That allowed me to start using the system as it was prior to running the upgrade, and all is working fine.
In terms of upgrading, I may try again, but not until I have a few hours to fix problems if they occur. I am not particularly happy with how the upgrade to 11.5.1 went. Usually they are pain free and just work. This one failed miserably and at least it wasn't just me that had the problem. I suspect there must be a problem somewhere with their upgrade.
I'm not sure what caused it in the first place - I did run the upgrade via Terminal Services, so not sure if that was part of the problem. I read on another post that another person had a similar problem and also ran the upgrade via Terminal Services/Remote Desktop. Did you run it via TS/RDP too? When I did the "rollback" described above, I did it all sitting at the console to be safe.
I'd be really interested to know how you get on, and if anyone else has had similar problems, and how to get the upgrade to work.
Regards,
SMST.