500 Internal Server Error installing codeigniter on ubuntu 11.10
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I have developed my codeigniter project on windows, now I am putting it on the server which is Ubuntu 11.10
I put my root folder in 

> var/www 


when I access my localhost through the web browser it displays the login page correctly, but when I try to log in, it displays 

> 500 Internal Server Error

when I look at my /var/log/apache2/error.log
 it displays the following:

> [error] [client 127.0.0.1] Request exceeded the limit of 10 internal redirects due to probable configuration error. Use 'LimitInternalRecursion' to increase the limit if necessary. Use 'LogLevel debug' to get a backtrace.

Any idea of what may have made this, and how to solve this problem???
Thanks in advance 