Help with userclass, form checking, and header

I seem to be having some trouble with my PHP code. Was wondering if someone could help me sort them out…
One issue is that my session variables don't seem to be registering. I place a value inside a session variable to hold errors, but when the user is taken back to the index page the error isn't displayed in the error handle.
A second issue is even though I've check a session variable to not be equal to something the header fires the redirect anyway…
hmm… I've also got this section of…
Help with userclass, form checking, and header

See original post by Jeremy Benson