Problem
A project password cannot be cleared, even though all secure devices have been removed from the project.
Cause
ETS uses the project password to encrypt security credentials. As long as the project contains anything related to KNX Secure or KNX IoT, the password is still needed. ETS then won’t let you clear it, even if no secure devices are left in the project.
Conditions required to clear the project password
The option to clear the password only becomes available once every security dependency has been removed or set to plain:
- IP Backbone security: Security on the topology backbone must not be set to On. Set it to Off or Automatic, so that it resolves to plain.
- Group Addresses: No Group Address may have security set to On. Set all Group Addresses to Off or Automatic, so that they resolve to plain.
- Device certificates: The project must not contain any device certificates. This includes unassigned certificates. Remove every imported certificate from the list (see here).
- KNX IoT and secure group objects: The project must not include KNX IoT devices or any group objects that require security.
- Device download state: No device in the project may still be in a securely downloaded state, for example with a loaded tool key, backbone key, authentication code or management password. If secure devices were already commissioned, download them again in plain mode or unload them first.
Resolution
- Check the project against all of the conditions above and correct anything that doesn’t meet them.
- In ETS, open the project and go to Project Details / Project Settings → (Change) Project Password.
- Click Clear Password / Reset (see here).
Verify the above and try again via the 'Clear Password' button. See here.