Admin Modules Crashes

After rebuilding my system using 4.5.0, admin/modules seems to crash when certain modules are included in the modules directory. Including a custom module that I built for my system. If I remove the problem module from the directory admin modules works fine and displays a list of the modules. However with it in place, the command seems to crash resulting in a "page cant be displayed" error to be shown in the browser. Similiar issues exist with other 4.5.0 released modules from the download page including the filemanager module. No errors are being logged to the webserver log. So I'm stumped as to where to look for the failure source. Any ideas?