http://www.vbsquare.com/tips/tip317.html

I've used this tip before without any problem, but could someone explain how to expand this to allow characters like the return or the period key to not be blocked out?

Also, is there a way to stop it from causing a beep on bad character input?

Also a general explanation of what is going on would be helpful. I understand that some sort of bit masking is occuring, but I don't understand enough about the WindowLong parameter to fully understand what is going on.

Thanks in advance,
Dim A