Registry Tweak for Using Event Log in Orchestration
I often write to the Event Log in my orchestrations to provide simple progress statements or error messages. However, if you set up a BizTalk environment where you assign specific user accounts to the various BizTalk services and are NOT running under the admin account (which you SHOULDN'T be doing if you are trying to run under least privileges), you'll have to tweak the registry to use the Event Log.
If you see an error in HAT that says "Requested registry access is not allowed" and you break on an orchestration step that writes to the Event Log, change the permissions on the registry key at
to give full control to the user account that the processing host runs under. Then bounce the host and you should be good to go.