I've recently received a PM from someone who was trying to attach a file in a PM for another person, but they couldn't, because the other person had the ' symbol in their name.

I've also tried to reply someone's hosting requst recently,  but the person had \ in their name and phpBB said that the user doesn't exist. So, how will I PM this person?

In short, please, if your name contains weirdo characters like ' and \ which are extensively used in PHP language, please, eliminate them. Everyone is free to rename themselves here.