Windows – Backup failed with following error code ‘2155347997’

June 9, 2015

I have a System State backup failing for days on a Windows 2K8r2 server, giving an Event ID 517 error Sad smile


Quite a cryptic error code ‘2155347997’

After looking around on the interweb I found a lot of hotfixes and workarounds to get it solved. But I was convinced that none of those was really the root cause.

I had a gut feeling that lack of disk space would be a more reasonable cause of the failing backup.

I decided to start a manual backup using WBAdmin

But it did end into the same error ?

Next I decided to save the backup to a different server logical disk using this command :



And voila all went well Smile

Windows – AD Sync Msoidentitycrl Tracing Growing Rapidly

June 3, 2015

At some point I was surprised to see that my C: Drive on the production server was filling up rapidly ? Sad smile


After a quick analysis I saw that the reason was 40 Gb of msoidtrace tracing log files ?


After checking a bit deeper I could see that these where coming from the AD Sync Services we had installed lately.

Solution :

After applying the proper registry keys


And restarting the service “Microsoft Online Services Sign-in Assistant”


The problems where gone Smile

Read more here.

Enjoy !