Hi V_Pozidis, Hi Brian,
If you look at the _user table, you can see that the password for the user you have created has not been encrypted (see screenshot 1 in the attachment). This is because you have not used the standard MVD forms for a) creating new users (you must have ADMIN privileges to do that) and b) for changing your own password.
Therefore, when you try to login, MVD is, in effect, trying to decrypt a password that hasn't been encrypted in the first place and that's why you get the error.
As Brian has written, you must use the standard MVD forms when using the user / roles functionality. To create a new user, you must be a user with ADMIN privileges (see screenshots 2 and 3). Once the user has been created, that user can change his own password (see screenshots 4 and 5).
Derek.