I installed on this SD-Card numnerous European Updates WIT Garmin Express on the SD-Card using the SAME Thinkpad. All what I have done is to update Garmin Express. The SD-CArd ist still shown in WIndows explorer when I connect my NÜVI 756. I tried the Install too on a WIN10 PC, a new 16gb sd-card aso. I'm in IT business for 30 Years so I'm shure that I have'nt done something wrong. I'v read all the support docs on support.garmin - not very helpfull, so ??
Last try was to download the map to the PC and use garmin mapinstall for moving map to the Nüvi - no way.
In the end Garnin Express is buggy !
I know NÜVI 756 is a very old device - but its working still perfect.
So please - don't end support for this device in such a way!
It have to be said the the Nüvi can use the old, on SD-Card installed European Map without problems.