When I tried to Register DAEMON Tools, I got this message:

We do not accept e-mail addresses from free e-mail services
Free e-mail services are all I use, and some things that ShareIt has on the list of free services, are also pay services. For example, I pay for an upgraded Hotmail account, but I couldn't use that address to register either!
I have registered nearly all my software to "free" e-mail addresses with no problems. What's the deal here?

Is this a restriction that you can change?