Thread: Registration Error - Illegal characters?

Registration Error - Illegal characters?

I am getting an error when trying to register a new account that states: "ERROR: This username is invalid because it uses illegal characters. Please enter a valid username."
After doing some research on these forums it seems that it is an issue with multisite(which I have enabled) and not allowing uppercase letters. However most of the questions and solutions were geared towards classipress which I don't use. I am thinking an easy fix for this(if there is no way to fix it with code) is to add some text that explains to only use lowercase letters for the username. The problem is I can't figure out how to add this text to the registration page. Adding the text to the registration page in "pages" does not do anything and the default text still says "Complete the fields below to register."

1. How can I change "Complete the fields below to register." to add a note about using lowercase letters?
2. If it is possible is there some code that will change uppercase letters to be acceptable?(I don't have any php knowledge, all I can do is copy/paste).

Thanks.