After installing updates or making changes in your server, your application pools may stop working and throw “HTTP 503 The service is unavailable” error with this description: “Trying to read configuration data from file ‘\\?\<EMPTY>’, line number ‘0’“.
In the Event Viewer, you will see the event ID 2307:
The worker process for application pool X encountered an error ‘Cannot read configuration file due to insufficient permissions’ trying to read configuration data from file ‘\\?\EMPTY’, line number ‘0’. The data field contains the error code.
Getting HTTP 503 Service Unavailable (Application pool has been disabled) error? Check this post out.
Solve “Trying to read configuration data from file ‘\\?\EMPTY'” error
This issue may happen because of the problems occurred during virtual directory and application pool creation. Other possible cause could be the missing config files that might have been removed somehow (possible suspect: Antivirus).
Here are a few things to try to solve this issue:
- Remove everything in
C:\inetpub\temp\apppools. Restart the machine - Antivirus software may be removing the config files in the
temp\apppoolsfolder. Therefore, check antivirus software’s logs and define an exception for this folder if needed - Make sure
IIS_IUSRShas Read access on application folders that are referenced by virtual folders - Check if
IIS_IUSRShas access onC:\inetpub\tempfolder - Check that you have enough disk space in the server
- Run
chkdskin Command Prompt in the server. Afterwards, make sure fix the issues found - Try removing and recreating an application pool
- Try removing and recreating an virtual folder