So I used the Format option within the Windows OS.
First task after removing the card from the van, slide the switch on the side of the card to un-locked. Pop the VW card into the card reader or slot on your PC, my laptop saw this as D:\ Next, right-click the new drive (D:\ in my case) and select Format. Make sure the FAT32 is selected and I then selected Quick Format.
Once this completed I opened the DiscoverCare App and selected the non-VW card option, I de-selected Backup ( figured card was formatted so nothing to backup). The Download was either very quick or DiscoverCare could see the file from a previous attempt but the install to the card took a good 30-45 minutes but could have been longer , I wasn’t watching all the time.
Don’t forget to slide the switch on the side of the card to locked and pop back into the van.
This worked for me but I did need to setup my POI’s again after dropping the card back into the slot.
Don’t forget if you use a non-VW card then it probably needs to be a quick card, something like a Class 10, with at least 16Gb of storage.
If you go above 64Gb then the card probably needs to be Formatted as ExFat rather than FAT32. Not tested this so no idea if the VW unit will read a larger card, the VW card that I have is 16Gb.