Notice: Undefined index: REQUEST_URI

[Romeo30]

I have a problem and can not find where is it

I have this error all which are on the tracker

Notice:  Undefined index:  REQUEST_URI in C:\inetpub\vhost\max-area.org\httpdocs\include\bittorrent.php on line 496

Warning:  Cannot modify header information - headers already sent  by (output started at  C:\inetpub\vhost\max-area.org\httpdocs\include\bittorrent.php:496) in C:\inetpub\vhost\max-area.org\httpdocs\include\bittorrent.php on line 496

looked bittorrent.php and do not see any problem

I can not even log the same error