A file downloaded apparently successfully fails to accept authorization/crashes
The most likely reason for this problem is that the file has becomes corrupted or not fully downloaded and saved. This is known to be a problem where downloaded secure files are quite large and the telecommunications facilities are not very good – reports of this kind have been received from locations in Africa and some of the Pacific Islands. The solution is to find a location with better telecoms or to ask the publisher to make the file available via a different mechanism, e.g. via Dropbox or WeTransfer or SendNow etc., or on a USB stick.
Another possible explanation is that the file has downloaded OK but the local router or network security blocks the authorization process. For non-corporate environments try re-setting the router and/or data connection facilities you are using and then see if that resolves the problem.
See also the Help page, item 2: https://drmz.net/email-templates/help.html
For corporate networks that block access it will be necessary to enable access or use a license file, or use our web-based option provided at www.pdf2html5.com