Download HKCRScan.exe tool for troubleshooting MS Article ID 823159
Users were getting a "HTTP/1.1 503 Service Unavailable" on both https://<servername>/Exchange , https://<servername>/Public and on https://<servername>/microsoft-server-activesync, they get a login prompt and then a "HTTP 501/HTTP 505"
The below tool should be run from the command prompt. It should identify and remove registry keys over the 259 character limit. It will kick back any errors. If you have null keys (keys that are faulty but unremovable), you can use RootKitRevealer from sysinternals and get rid of them. I understand that regdelnull can do something similar, but in this case, it was a corrupt key, not a key with null characters.
In my case, the affected key was relating to the driver for the Intel storage controller (VEN_8086&DEV_24D3&SUBSYS_458015D9&REV_02). Not cool. I could not delete or rename the key and could not set/view permissions on it. Ran RootKitRevealer, which caused a stop error/reboot (crap) but successfully removed the key. IN OTHER WORDS, DO NOT DO THIS IF YOU DO NOT HAVE A TESTED BACKUP.
"To help troubleshoot this issue, run the HKCRScan tool (HKCRScan.exe). The HKCRScan tool enumerates the HKEY_CLASSES_ROOT registry hive to locate subkeys that contain more than 259 characters. Additionally, HKCRScan helps determine if there is an invalid discretionary access control list by returning error code 0x5. This error code means "Access denied" when it enumerates a registry key. The HKCRScan tool is an internal tool developed by Microsoft."
June 8th, 2010 - 00:07
Keep posting stuff like this i really like it