Getting 403 Forbidden from admin when accessing over internet

[robertbalazs]

Expected Behaviour:

Accessing Pi-hole admin page over the internet via external-ip/admin when port 80 (internal and external) is forwarded.

Actual Behaviour:

Getting 403 Forbidden on port 80. Only works if internal port set to 80 and external to something else, for ex. 225.
This way accessing over internet external-ip:225/admin works

Few mentions:

1. On older Pi-hole versions port 80 worked flawlessly
2. I have a same setup (same RPi, same DietPi os, same settings, same router brand, same internet provider) at my parents' house, and there admin on port 80 works as expected
3. I've tried reinstalling everything from scratch -> same results
4. I've tried with standard port forwarding and adding Pi-hole to DMZ -> same results
5. No other device is using port forwarding
6. No other service runs on Rpi
7. Locally everything works fine (local-ip/admin on port 80)

Thank you for help

Debug Token:

raqh766oqx

[DanSchaper]

I believe the URL for the admin page is different with DietPi since DietPi has a pre-configured HTML server. Did you install Pi-hole via the curl command or via the DietPi installer script?

[robertbalazs]

Reinstalled with curl command, now everything works as expected.
Thanks, the topic can now be closed/deleted