Error message - "The ACSM file you are attempting to use has expired"

If you get this error message when attempting to download an EPUB ebook - "The ACSM file you are attempting to use has expired. Please download a new copy of the ACSM from your original source" - here's what to do.

If you are travelling, make sure you set the clock, calendar and time zone on your computer or device to the location that you are currently in.

If you are at home, make sure that the clock and calendar on your computer are set correctly, and that you have selected the correct time zone.

Doing this should resolve the issue.