Posting Problems

I am having trouble with posting. I can type in the box just fine, but I cannot add smilies and I am unable to format the text by clicking the smilies/formatting buttons. Help!!
Also, I am a member of the FashionSpot, which is similar in structure to the Purse Forum... and I am able to post in the WYSIWYG format there without a problem. I am able to enhance text and add smilies there. Maybe this might not be just a browser issue?
I'm on Firefox, which is the latest version. It's strange that this version works fine on my Mac when posting on WYSIWYG message boards, but doesn't function on my work computer (Windows). I am able to post on the FashionSpot at work with WYSIWYG format though...that's why I don't understand why it won't work for me on TPF. Thanks, in any case!