Thank you. This issue has already been reported and our developers are working on it.
Well I doubt if it's going to be fixed yet
Even when you remove and delete the version of Garmin Express, then proceed to download from the Garmin source, you still receive the message 'Download Failed'.
When it's fixed, as there is no update stop worrying, once the update is released download from the Express website. It's not rocket science.
This issue has been resolved with the release of Garmin Express 6.21.0.
The installer may need to be downloaded from the Garmin Express website to update. Once updated, the check for updates no longer reports Download Failed.