Fail to delete files on external drive

[Pochacco16]

A task is created and executed every day for file backup to external drive. Post backup event is set to shutdown the computer and 2 copies are kept on external drive. However, it is found all backup files are kept and it seems cobian reflector won't delete any files on my external drive. Any clue? Thank you.

[cobian]

This is a known problem. Should work if the computer is not shut down but the deletion is interrupted otherwise.