Hi Catymag,

Thanks for the info - boy Garmin software is flakey - or at least it is on a Mac - simple procedures like a map update become major issues taking hours !

I have made some progress. I ejected the SD Card from the Nuvi, placed it in a card reader then connected both the card reader and the Nuvi to the Mac.

I then launched BaseCamp and it managed to load the map data from the Nuvi/SD card without ejecting them both.

I then launched Express and started the process of re-installing NTU 2015.40 I found the "view details" page and this gave me the option of installing the map to Nuvi/ Nuvi + Computer / Computer. I selected the computer only option and it did successfully install the map to BaseCamp (despite the map already being installed on the Nuvi SD card). So it appears, fingers crossed, to be working.

One other thing I did though I haven't done on previous map updates was to log on to the Garmin website, put in my serial number and request an unlock code. This downloaded an unlock code to the SD card. I don't know if this was necessary ( I have Garmin lifetime map updates for Europe) or if it was the thing that stopped Garmin Basecamp ejecting the discs.......