I have a problem with CodeIgniter .htaccess file and hope that somebody can help me! I don\'t know regular expressions or how to use the .htaccess, I\'m very new with this t
First of all this is redundant:
RewriteCond $1 !^(index\.php|images|robots\.txt)
because your other conditions already take care of existing files and directories so I'd suggest to remove it.
Your rewrite rule is wrong if you want /admin to rewrite to admin.php, with your current rule it will result in /index.php/admin. You didn't mention if that's the problem, if it is do this:
RewriteRule ^/admin$ admin.php [L,QSA]
RewriteRule ^(.*) index.php/$1 [L,QSA]
Also you can debug the rewriting using RewriteLog: http://httpd.apache.org/docs/2.0/mod/mod_rewrite.html#rewritelog
If that doesn't fix it please describe the current behaviour and what you expect, otherwise it's difficult to help.