What happens during install map to PC?

[Peobody]

I was just thinking about the install map to PC process and wondering how it works. I know that a device like the XT can update its map via wi-fi with an internet connection. What I don't know is what is happening when the map is being installed to the PC by Express. Express requires that the device be connected so I had assumed the Express contained a map installation routine that installed the map on the device onto the PC. That thinking seems flawed based on how long the process takes. It seems that another download is taking place which would explain the reference to "MSI" in a log associated with the last failure I experience. I would be grateful for an explanation of the install map to PC process.

[sussamb]

Well first you can install the map to your PC without a device connected, I do it all the time.

As for the process, what happens first is that Express downloads numerous files to your PC. Often folks complain of map installs failing at 50%. This happens because Garmin defines the 50% point once these files are downloaded, and then those files are installed to your PC in a way that BaseCamp, and indeed MapSource for those that remember that program, can read and display the map. This requires user input in that Windows UAC kicks in to check that you want Express to make changes to your PC, failure to allow this means the install fails but many leave their download running and walk away, then wonder why it's failed when they come back.

[Peobody]

As for the process, what happens first is that Express downloads numerous files to your PC.

Once these files are downloaded, is there one that can be run independent of Express in the event of an installation failure, a .exe or .msi perhaps?

What is the path these files are written to?

[sussamb]

Unfortunately not

[lkraus]

Once these files are downloaded, is there one that can be run independent of Express in the event of an installation failure, a .exe or .msi perhaps?

What is the path these files are written to?

I have not found a way to use the files again after Express is finished with them, but Express does not delete them when it exits. They remain until the next upgrade and sometimes, if the install goes wrong, the old versions just accumulate.

I've found many such useless files in "C:\ProgramData\Garmin\CoreService\Downloads", typically about 5 GB worth, but sometimes as much as 16GB. (ProgramData is hidden.) The wasted space does not matter on my desktop, but my travel netbook has only 48GB of space on the C: drive and I have to delete that Downloads folder after every map update (and move the map to D:).