Not all albums shown under Windows

[peter.muller@synctel.be]

I installed MinimServer on my windows 10 PC, allowed it to complete the scan and when it informed me it was online I used the HEOS app from DENON to connect to MinimServer (which appeared under the list of media servers - it is the only one present). The search worked fast and music played perfectly, however I noticed that about half of the "Albums" (which are just folders on the disk pointed to during setup" are not showing up. An example is Elton John Jewel Box Disk 6 and Disk 7. Disk 7 shows up, but Disk 6 does not show up. I checked the properties of the individual tracks in the respective folders and the Volume information is registered correctly. There are many other cases of the same thing happening. What am I doing wrong?

Many thanks
Peter