Yes, I have javascript enabled and have cleared my cache, cookies many times since this started. But I think I may have stumbled on the cause. Another thing both of my computers have in common is LastPass.

I can use any of my browsers in the private browsing mode wherein add-ons are disabled and can hen open the posts in the forum and read them. However, I tried copying my password for this site from LastPass BEFORE putting the browser into private browsing, and then pasting it in the signin box in this forum so that I can start a new thread, and I still CAN NOT start a new post. Then I will get the dreaded page telling me: "Unable to load webpage because the server sent no data."

I went to the LastPass forum last night when I stumbled upon this and see that I have received an email from the forum so I will go check that out.

I had to Google this since I didn't know what you meant when you said to flush the dns cache. From the instructions I found, I would have to use the command prompt.

Is it totally safe for me to do this? I mean, I won't end up with no connection at all, or something, will I?

The command shown was ipconfig /flushdns

I did it. It didn't make a difference on this site I've been dealing with, but the more that has happened, the more I know it's the site that is all messed up. A gal from the AV forum who had actually been able to get in and open and read posts registered for me so that she could tell them what was going on -- since I can't. After she registered, she could no longer even open a post -- just like me. I've written to this company so we'll see if anything comes of it.