Cannot log into existing installation

[saint]

I have uploaded the debug mode plugin.

Since I cannot access / log into the my installation - I assume that I edit the gsconfig.php file to enable debug mode ?
I remove the # from in front of this line -> define('GSDEBUG', TRUE);

Example :

# Turn on debug mode

define('GSDEBUG', TRUE);

if the set up I describe is correct, how do i get the debug readout ?

Also,

I only deleted the user management php file in the plugin folder. No other file was deleted.