I think you may be confused about the link I'm referring to. The problem is not logging in or out of Disqus, Twitter, Google, etc. The link I am referring to is the one that gives you the option to log into the website, with the link text being the website name. Here's an image of what I see:
[IMG]http://i.imgur.com/jdkseXu.jpg[/IMG]
If you copy the link address without clicking it, it copies this:
However, when you click on it, it gives you a pop up window that does point to my site, to this link:
http://www.echoparkforums.com/blog/wp-login.php
Now that I tried the pop up link, it worked, and I haven't changed anything--i don't know why it works now.
But before, it led to the 500 at this address. And when copying-pasting the address on a regular browser, it would take you to the link/login.