How do I change the temporary directory without using any administrative pages provided by Drupal? I've moved my live Drupal website to Windows localhost (XAMPP), but I'm getting lots of "The file could not be created" errors. If I log in to the site as an administrator, it fails to return any more pages at all. I can view it with errors if I don't log in. 

Is there a way to change the temporary file location without logging in through the interface, or using any administrative page?
In Drupal 7 the temporary path is stored in the variable file_temporary_path, so you can either update the entry in the variables table with a SQL-query. Or you can use Drush:

drush vset file_temporary_path [some_new_path].