I have no idea where to post this,While trying to free up space, I discovered a 300MB hidden file called san_test.tmp on my C drive. (directly on the drive, not in any directories) So my question ...

Click "OK" and click "Delete Files" button in the prompt that appears to remove the Plug TMP files from your computer.

Deleting the tmp directory; workaround We previously reported that in rare instances, Safari can delete a user's home directory when attempting to download a file with the option-click command.