When using a windows application (e.g MS Word 2013) to print to pdf using the Acrobat print to pdf driver, the resulting file cannot be deleted. It says that the file is being used by Adobe acrobat. Even after the program is closed, the error remains. A reboot does not clear the error, i.e. after reboot, you are still unable to delete the file. The only way to delete this file is to enter the task manager and kill the acrobat process. Win 10 1809