Thread:Project:Support desk/Upgrade from 1.5 to 1.14 fails.. nothing on screen/reply (3)

Having absolutely nothing on screen usually indicates a php fatal error. This could be caused by an extension not compatible with MW 1.14, or potentially some config setting that doesn't work with newer mediawiki but did with 1.5 (Generally we try to be careful to make sure we retain backwards compatibility in regards to config settings, or at least fail nicely, but its always possible for something to be incompatible)

It would be helpful if you could put the following at the very top of your LocalSettings.php file (right after the  and before anything else): error_reporting( E_ALL ); ini_set( 'display_errors', 1 );

This would hopefully cause your install to give an error instead of just a blank page. From there we should be able to further track down what the actual cause of the error is (See manual:How to debug for more details on debugging)

p.s. As Hazard-SJ said, MediaWiki 1.14 is still what we'd call an "ancient" version of MediaWiki. Since you're upgrading you may want to consider using 1.18.