Sloppily.
I recently tried to convert my main site to WordPress, installing a new WP in a new directory. I was trying to refresh the site’s appearance with WP themes.
I used the Make theme and got a front page I liked. This was just a test, so it wasn’t live and I forgot about my WordPress site experiment.
Except that WP used some of the existing database in special ways.
The result? My WP blog which has run flawlessly for years disappeared. Blank screen. No images. No posts. No menus. Remember that Borges story about the ink-drinking monkey? It’s my WordPress install!
After trying a bunch of things for several hours: turning on debug messages, turning off plugins and my current theme – no help. (And what is my latest theme anyway?? To find that out, I used a site that reads WP themes from any webpage; it assured me I wasn’t running a WordPress blog. That was … comforting.)
Anyway, the solution was to go into my cpanel and read the data in my MySQL database. There the blog site’s address was confused with my main site.
(I got that idea when trying to load myblog.com/wp-admin directly into my browser — the blog’s blank — and being sent instead to my main site’s WP installation. The database redirected me to what it thought was my blog.)
I think I can use WP successfully on my main site and my blog site, if I assign each WP instance its own database. Duh. The reason the new WordPress on my main site didn’t APPEAR to mess up was that I created a new static home page and didn’t go to blog pages — where my current blog would have appeared.