problem with CAPITAL letters

Hi again
Before update I had lot of users with capital letters in username. It looks like user have Username with capital letter in Joomla, but username without it in moodle. It worked fine, but I think only before moment when someone choose existing username, but without capital letter.
Now in new joomdle version we have great plugin that forbid capital letters at all. But now my old users with capital letter can't login.
So I tried to change capital letter in user name manually, but site told me that I already have this user in moodle (of course I have because moodle username havenot capital letters at all ).
How can I easily solve this?

You can disable the user check plugin while you do the changes.

It works, thank you )
But maybe you know how can I change all capital letters in usernames globaly?

I don't know what you mean with change all capital letters golbally.

I mean, can I write script that search all usernames in joomla (maybe in joomla database) and replace all capital characters. Or I need something to do in joomdle and in moodle databases.

You could write a simple php script to do it... possibly you could even do it with a sql query directly.

That said, I don't understand why old users with caps cannot login anymore. User check plugin does nothing on user login.

Fastest and easiest way is to use your phpmyadmin or other mysql admin client and run a MYSQL update with UPPER.

I don't know why, but then I try to recover user (with uppercase symbol in username) site told: "The username can only contain alphanumeric lowercase characters, underscore (_), hyphen (-), period (.) or at symbol (@)"

What do you mean by recover a user?

I mean, that I try to recover username or password via frontend jomsocial form.
(Click on "Foget login?" or "Foget password?")