Changed General Settings, now have a problem

Hello,

I recently changed the permalink structure for a friend’s site under the wordpress dashboard for general settings to just the name of the site, like this example: something.com.

This was under the wordpress Address URL and the Site Address URL. Both fields originally said: something.com/wordpress

I also changed the permalinks settings to post name so that the links on the site could be customized with /%postname%/. Once I made these changes and then logged out I now can’t log in again. I keep getting a page 404 error. It also says I may need to rename the htaccess file. What do I do to correct this problem? I think I may need to change the .htaccess file. If so, how do I do that and what lines of code do I need to include in it, if needed, to fix this? The site is being hosted at Network Solutions. I didn’t have this problem with my own site under Godaddy.

Thanks,

Rob