Now my visual editor works, but I can't click into any of my blog posts

have you tried:

1. deactivating all plugins to see if this resolves the problem? If this works, re-activate the plugins one by one until you find the cause.

2. switching to the default theme to rule out any theme-specific problems? If you don’t have access to your admin panel, access your server via FTP or SFTP, navigate to /wp-content/themes/ and rename the directory of your currently active theme. This will force the Default theme (Twenty Ten theme) to activate and hopefully rule-out a theme-specific issue

Actually, every link to any specific post is broken, I don’t see how messing with themes and plug-ins is going to help. But I just deactivated all my plugins, no effect. I renamed the theme directory, and then I couldn’t get to the site at all.

It seems like somehow the database has been corrupted? Links to specific posts that worked just fine a week ago now show 404 errors, here’s an example: https://blog.kirkpetersen.net/2010/02/honest-labor-from-mach-2-to-muenster-to-madison.html

Fixed! It turns out it had nothing to do with plugins or themes. Because I had followed exactly the previous advice given, “delete then replace your copies of everything except the wp-config.php file and the /wp-content/ directory with fresh copies,” I lost my .htaccess file. Luckily I’d kept a complete backup of my blog from before the upgrade on my hard drive and was able to retrieve it from there. Everything is working now.

Glad you got it sorted out.
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