I see you're missing .png and .jpeg from your list; its not case sensitive, so all you need is:
.gif,.jpg,.jpeg,.png

Then whatever file attachment extensions you want to support such as:
.css,.txt,.pdf,.gz,.rar,.tar,.tgz,.zip

UBBDev uses:
.gif,.jpg,.jpeg,.png,.css,.txt,.pdf,.gz,.rar,.tar,.tgz,.zip

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
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