Mod-rewrite.htaccess not working - php

Question

Hi I previously posted a question on to Stack Over flow and was lucky enough to receive some assistance to my initial question which helped me better understand that what i was trying to achieve was possible.
The previous question is here: Visit php url shortening
I am building a system where users can share their profile on other websites so i am wondering is it possible to shorten the actual url which would provide a link to their profile which would be something like this, www.somedomain.com/users/profile.php?user=myusername to simply cut out the users folder and the profile page and so something like this: www.somedomain.com/myusername
the code I have is:
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule /(.*) /users/profile.php?user=$1
Sadly two things happen, firstly the code doesn't work and secondly when i add this code the css on the original long domain stops working.
Any suggestions would be appreciated

Answer 1

code doesn't work: of course it won't because it's incorrect. Really wondering how did you end up accepting other question without properly testing it. Anyway take this code and replace your existing .htaccess code:
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php/?$ - [NC,L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l
RewriteRule ^(.*)$ users/profile.php?user=$1 [L,QSA,NC]

Answer 2

This is serverfault question.
Are your running apache?
Are apache mod_rewrite module enabled?
debian: a2enmod rewrite; /etc/init.d/apache2 restart
Are enabled override for this directory? In case using default vhost:
<Directory /var/www/>
#AllowOverride None
AllowOverride FileInfo
</Directory>
What are showing error.log?
tail /var/log/apache2/error.log
Try simple version:
Code:
RewriteEngine On
RewriteBase /
RewriteRule ^profile.php profile.php [QSA,L]
RewriteRule ^(.*)$ profile.php?user=$1 [QSA,L]