In 2004 I burnt a double layer DVD containing a lot of useful stuff. When I came to read it this year, Windows 10 saw the DVD as blank. Had the disc deteriorated over the past 14 years? I tried it on another Windows 10 computer, and again it saw the disc as blank. I then found an old Windows 7 computer, and it could read the disc perfectly.
I then tried to read the disc using a Windows XP virtual machine in VirtualBox, running on my original Windows 10 PC, and to my amazement it worked straight away. I thought there was a chance it would work if I turned on the Passthrough option for the DVD drive, but it didn't even need that. Testing further, I found it also worked in Ubuntu and ReactOS virtual machines.
I cannot fathom how the disc cannot be read by Windows 10, but can be read when Windows 10 "shares" its optical drive with another operating system. I haven't seen reports of anyone else encountering this problem, and it seems unlikely that the capability has been removed from Windows 10 without anyone noticing. If you can explain it, please send the answer on a postcard.
Update (14 July 2018)
To add to the confusion, I was able to burn a new double layer DVD on Windows 10, and read it successfully. Both the readable and non-readable discs are the same brand of DVD+R Dual (double) Layer disc, and the same ISO9660 / Joliet file system.