If you are getting an error logging to the EventLog, make sure you have the following registry setting:
- Navigate to \\MyComputer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\
- Right Click on EventLog and click permissions.
- Add the service account (application pool ID or BizTalk host instance service account) to the list of users and give it a special permissions of (Query Value, Set Value, Create Subkey, Enumerate Subkeys, Notify, Read Control).