Running as network service user fails (Windows)

[mistoll]

On windows I want to run mosquitto as user "network service". When changing the user of the mosquitto windows service to "network service" the service fails to start.

To narrow it down I tried to start it manually:

1. Start "cmd" as user "network service". I used "devxexec.exe /user:NETWORK_SERVICE cmd".
2. Run mosquitto with config file:

> "C:\Program Files\mosquitto\mosquitto.exe" -c "MY_PATH\mosquitto.conf"
1695297547: Error: Unable to open log file MY_PATH\mosquitto.log for writing.
1695297547: Error: Unable to open pwfile "MY_PATH\passwd.txt".
1695297547: Error opening password file "MY_PATH\passwd.txt".

When I remove "log_dest" and "passwd_file" then mosquitto starts correctly. And so does the windows service.

Both files are opened using mosquitto__fopen with restrict_read=true. I assume it has something to do with the code setting the read restrictions.

Of course I tripple checked the file permission. For example echo "test" > MY_PATH\mosquitto.log works as expected.