Hi,
I tried to change my email address with the forum User Control Panel and after a number of 'wrong password' errors, I remembered that there is a seperate service for our email/passwords to our accounts (actually I don't know about password but email cannot be changed in the forums for sure)
If that specific page were locked (say, text boxes greyed-out) or at least had a warning that the feature is disabled, users wouldn't get confused about it not working. Instead they'd be directed to make the changes at identity.mageia.org.
Thanks