Geez, it’s heart breaking to read this thread. I’m experiencing the same problem of .htaccess not being writable (despite permissions), but with a minor variation: when I change the permalink structure, WordPress fails to write .htaccess silently. That is, it doesn’t even tell me that it couldn’t write to .htaccess. I check the contents and date stamp of .htaccess via FTP and I discover that no changes were made.
I noticed the problem first when I tried creating a new page about a week ago. I don’t know when I last (successfully) created a new page, but I upgraded to WordPress 1.5.1.3 on 5 July 2005, and the latest timestamp of my .htaccess was 17 July 2005. So sometime between 17 July and now, my WordPress’s ability to write to .htaccess broke. My permissions on .htaccess are (and always have been) 666.
I thought that maybe I need to upgrade to 1.5.2, but this thread seems to indicate that I should try downgrading to 1.5! I inquired with my hosting company (monsterhosting.ca) to see if they had changed anything on the server, but they denied making any changes.
It’s frustrating because it used to work, but now it doesn’t. I’m stumped. And editing .htaccess by hand is not a great solution.