Problem with attaching files...?

I started a new thread for a problem I had with a malware issue and I had attached three different logs without a problem. Now, when I following the instructions of the reply I got and went to attach the new logs I don't have any attach button. I deleted all of my old attachments under User CP but I still don't have an attach button in Firefox, just the text "Valid file extensions: bmp doc gif jpe jpeg jpg log pdf png psd txt zip" in the Attach Files box. When I try it in IE I have a button but when I click it I get a new window that says error loading page. I'm sure it's something stupid but what am I doing wrong?