#Microsoft, #Skype: this is very stupid.
What comes before the `@` in my email address is… a single character. You're banning a letter of the alphabet for me.
You're preventing me from using a very robust, completely new password — so now I have to make some contortions (and most importantly, _remember_ those contortions) to adapt my usual password strategy to this silly requirement.
@tripu This wouldn't even be hard for them to fix: just silently waive that rule if the username is shorter than, say, four characters.