I have both MapSource and BaseCamp installed on a couple of PCs running Window 10. I have lots of mostly European maps installed, 23 on one PC, originally installed by MapUpdate and more recently Express on the D:\ drive and linked via shortcuts from the C: drive in the usual way. The D: drive maps date from 2014.10 to 2019.10. I maintain three (surviving) Nuvis using these maps. I also have a US map that came with a now deceased device. They have all been unlocked and used at some time.
Now, after a long period with no problems, neither BaseCamp nor MapSource can see most of the maps. They both recognise only one: City Navigator Europe NTU 2018.20. There are more recent Europe maps, including 2018.30, 2019.10 and 2019.20, installed by Express in the same manner, but these are not visible to either BaseCamp or MapSource. If I open the Map Product Manager, it shows me that the visible map is Unlocked and installed on D:\ProgramData... the same as the others. In the Unlock Regions tab, there are lots of Map product not installed entries, with comments like Region unlock code from gobblydegook-guid.gma.
I have recently used Express to update the map in one of the Nuvis to 2019.20, and this was installed on the D: drive at the same time. Neither MapSource nor BaseCamp can see it. It makes no difference whether the Nuvi is connected or not. There were no errors during the installation, and on disk it looks OK, as do the other maps.
I have uninstalled BaseCamp v4.7.0 and re-installed v4.6.2 and also uninstalled MapSource v6.16.3 and reinstalled with no improvement.
I suspect that the reason for these problems is my associating my logon with a Microsoft Account, which I did earlier this year, but I've no idea if so or how to correct it.
Any suggestions gratefully received.
Thanks,
David