Hopefully I can get some help with this.
I just installed WordPress, and I'm trying to set up permalinks to just be /archives/postname. My first step was to just choose one of the "common settings" so I chose month and name (http://www.cheryltullis.com/2009/08/sample-post). It said that because WordPress couldn't write to my .htaccess file I would need to manually change it. I logged into the cpanel of my host, and there wasn't an .htaccess file already created. So I followed the instructions on http://codex.wordpress.org/Using_Permalinks, made a blank 1.htaccess file, uploaded it, then changed it to .htaccess from my cpanel.
After doing so, my entire site went error 500 - including the WordPress admin area. According to the "using permalinks" page, if I get an error 500 I should delete the .htaccess file...so if I do that, the site works, but I can't change my permalinks. Any help would be greatly appreciated.