I searched the forums for this, and did find people having similar problems, but none of the suggested solutions are working for me. My problem is also a bit different, too.
I have a slightly active blog (at least one topic is pretty active with 200+ comments) - http://www.motherfathercockerspaniel.com. I recently moved it to it's own domain hosting plan (it used to be a domain pointer hosted with another domain). I followed all the tutorials for doing this move and everything went fine (a small glitch with a SQL error on import, but my host support spotted it for easy resolution). However, now no one can post comments to the blog (not even me). I can edit posts, publish a new post, and even edit previous comments, but I cannot post a new comment. I end up with a "Page cannot be displayed" error and then if I do a refresh I end up with a blank white page. The comments do not post or go to the moderation queue.
I tried a fresh install with a new database (importing nothing and keeping everything default -- no themes, no plugins, etc.). Same issue: I can post a new article, I can edit the default article, and I can even edit the default comment, but I cannot post a new comment.
I'm getting no error messages. I've cleared the /wp-content/cache, cleared my browsers cache, logged in through my dial-up ISP on three different computers, tried 2 different computers on my broadband, and 4 site visitors have reported to me that they cannot post either. I am using IE6 on all the computers I tried. I am not interested in installing and using FireFox or some other browser, since it is not the industry standard and not what 99.99% of my visitors are using.
From searching the forums, this comments issue seems to be pretty rampant and popping up out of nowhere, but there seems to be a lot of causes and a lot of different solutions. The fact that the exact problem persists for me with a plain vanilla install of WordPress tells me it's a WordPress coding issue. I'm starting to consider going back to an older version of WordPress, as I didn't start having these types of weird issues until updating to 2.0.2 (and now 2.0.4).
Any thoughts or ideas would be appreciated. Thanks in advance!