404 on all WordPress pages

did you accidentally change the way your permalink structure is setup? or maybe you just need to set the permalink structure.. sometimes turning it off and then back on fixes the 404 issues

Thanks for your suggestion! I’ve tried changing the permalinks (on all sites) with no effect. Anything else I can try?

Oh, and I’ve also tried restoring the mysql database from backup, and that didn’t help either.

Ah, this might be a clue:

I had a line in .htaccess to redirect index.html to index.php (to cope with some people’s old bookmarks to an old static page). Without it, I should expect a 404 for the non-existent index.html. But if I take it out, I actually get a 404 for index.php. Which means the redirect is still happening. Which suggests that there’s some other .htaccess file or something somewhere?

OK, it looks from the error logs as if all requests are being redirected to index.php in my home directory (public_html/index.php).

I don’t see anything that would do this in my .htaccess:

# These bits make WordPress ignore the specified password-protected directories

ErrorDocument 401 /failed_auth.html

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_URI} ^/(client1|client2|client3|client3|(news|services|careers|clients)\/files|failed_auth\.html).*$ [NC]
RewriteRule . - [L]
</IfModule>

# Redirect old intranet bookmarks
# 301 Redirect Old File
# Redirect 301 /intranet/index.html https://www.mysitename.co.uk/intranet/index.php

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# uploaded files
RewriteRule ^([_0-9a-zA-Z-]+/)?files/(.+) wp-includes/ms-files.php?file=$2 [L]

# add a trailing slash to /wp-admin
RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule  ^[_0-9a-zA-Z-]+/(wp-(content|admin|includes).*) $1 [L]
RewriteRule  ^[_0-9a-zA-Z-]+/(.*\.php)$ $1 [L]
RewriteRule . index.php [L]
</IfModule>
# END WordPress

Aha, figured it out. There was supposed to be an index.php in the home directory, containing calls to WordPress functions, but it didn’t exist. Restored it and all works fine again.