Blank Template Admin Pages

Symptoms: When you try to access your template admin pages within Drupal (/admin/themes) you get a blank page.

Under "administer » logs" you might see the error:
call_user_func(Copy of phptemplate_templates): First argument is expected to be a valid callback in E:\DomZeus\wwwroot\modules\system.module on line 572.

This happened around Drupal 4.7.3.
Basically if you have a file like "Copy of phptemplate.engine" in your "wwwroot\themes\engines\phptemplate you will get that error.
Backup that extra file and then delete it. You should be back in business...

This technique should also

This technique should also be used in your templates folders (like themes/chameleon ...etc...).

Bascially erase any file/folder that should not be in your template folder.

One person was having problems because of the extra folder FrontPage extensions create. In that case, try erasing the FrontPage extensions folder _vti* (_vti_cnf ...etc...) and any other file or folder that are none "standard" in your template folder.