Many thanks for the detailed explanation. (I did not realise the plugins were relevant to a bog standard FB install)

With Firebird 3, the users are per authentication plugin. By default
Firebird 3 has two distinct authentication plugins: Srp and Legacy_Auth.
You have now changed one SYSDBA (check the UserManager setting in
firebird.conf to see which), while you're authenticating with the other.

You need either need to make sure you either change both SYSDBA
accounts, or disable the least secure authentication model (Legacy_Auth)
by removing it from the `AuthServer` setting.

To change both SYSDBA users, make sure that the UserManager setting in
firebird.conf is set as:

UserManager = Srp, Legacy_UserManager

Then restart Firebird and use

alter user sysdba set password 'newpassword' using plugin Srp;
alter user sysdba set password 'newpassword' using plugin
Legacy_UserManager;

If you leave off `using plugin ...`, the default user manager is used
(which is the first in the UserManager list).

Alternatively, consider dropping the legacy sysdba account so you only
retain the more secure Srp account

drop user sysdba using plugin Legacy_UserManager

Only do this when you don't use tools or drivers that still rely on
legacy authentication.

Mark
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Mark Rotteveel

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