Can't post on forum

I've tried replying to posts and making a thread for days now (in general, rabbit chat, and rabbit health) and when I click submit it just goes to a blank white screen. This happened on another forum I'm on too. Certain parts of the forum I could post in just fine but other ones would just go to the blank white screen when I try posting. Why is this? :? I've tried deleting the cookies on my PC and it doesn't help so thats not it. Sorry this is in the wrong forum, I tried submitting this in the forum help section and several other sections and PMing it to admin but it went to the blank white screen everytime.

Have you tried deleting all your temporary internet files?
http://support.microsoft.com/kb/260897
Then log out and close your browser.

If this doesn't help I'm not sure :?

You've not got Norton running have you? If so - try disabling it.

I used to get problems with forums when I had Norton so I got rid and use AVG now.

If it's not that - I pass, sorry!