Still at it. Still not resolved. I've tried many solutions. Here are clues:
- If I go through a proxy server, I can sign in.
- If I use a browser I haven't used lately, I can sign in.
What doesn't fix it:
- Adding code as suggested to wp-login.php
- Removing code as suggested from wp-login.php
- Replacing the wp-login.php file
- Clearing cookies
- Renaming the plugins folder
- Renaming the theme folder
- Re-creating the username/password in the database
It's just a login. Where is it broken? Again, all my other Wordpress sites are just fine.