Error trying to update CN 2019.20 on Computer

Dears

I have the same error as described in the original post: when trying to install CN 2019.20 on my PC (installing CN 2019.10 some time ago worked well though). As the installation of CN 2019.20 on my Garmin device (Drive 51 LMT-S EU) runs without error, I suspected my PC to be the root of all evil. And after 3 days of trial & error, I decided to go for a “clean” installation. Just to discover that the error in Garmin Express persists ….
Here are the cornerstones:

• Windows 7 SP1 Home Premium 64bit (German) with latest Microsoft patches installed
  
• Clean OS installation (“from scratch”, done less than a week ago) with no Antivirus or Firewall installed
  
• .NET 4.7.2 (DEU)
  
• Garmin BaseCamp 4.7.0
  
• 39 GB free disk space, 8 GB RAM
  
• High-speed Internet access with 150 Mbit/s downstream, connected via LAN (no WiFi)
  
• Garmin Express 6.5.1.0 (auto-updated from 5.4.0.0) – same error with Garmin Express 6.8.1.0 though
  
• My User Account has Administrator permissions - and in addition Garmin Express is run as Administrator
  

The Express.log from C:\ProgramData\Garmin\Logs is attached. What caught my attention are the following errors around “EndpointNotFoundException” for “IElevatedInstallerService”:
2018-09-23 10:41:41.8622 | 17 | I | Launching elevated installer from C:\Program Files (x86)\Garmin\Express Elevated Installer\ElevatedInstaller.exe
2018-09-23 10:41:45.5090 | 1 | I | Opening channel to elevated installer service.
2018-09-23 10:41:45.6182 | 1 | W | Unable to find the endpoint for IElevatedInstallerService.
2018-09-23 10:41:45.6182 | 1 | W | EndpointNotFoundException
2018-09-23 10:41:45.6338 | 1 | W | Retrying...
2018-09-23 10:41:47.7242 | 5 | I | Successfully opened channel to IElevatedInstallerService.
2018-09-23 10:48:18.5984 | 1 | I | Shutting down the elevated installer
2018-09-23 10:48:18.6920 | 1 | D | Page changed to DashboardViewModel
2018-09-23 10:48:18.9155 | 2 | E | Exception thrown by unobserved task.
System.ServiceModel.FaultException: Der Ersteller dieses Fehlers hat keinen Grund angegeben.
bei System.ServiceModel.Channels.ServiceChannel.HandleReply(ProxyOperationRuntime operation, ProxyRpc& rpc)
bei System.ServiceModel.Channels.ServiceChannel.EndCall(String action, Object[] outs, IAsyncResult result)
bei System.ServiceModel.Channels.ServiceChannelProxy.TaskCreator.<>c__DisplayClass7_0`1.<CreateGenericTa sk>b__0(IAsyncResult asyncResult)
bei System.Threading.Tasks.TaskFactory`1.FromAsyncCoreLogic(IAsyncResult iar, Func`2 endFunction, Action`1 endAction, Task`1 promise, Boolean requiresSynchronization) bei System.ServiceModel.Channels.ServiceChannel.HandleReply(ProxyOperationRuntime operation, ProxyRpc& rpc)
bei System.ServiceModel.Channels.ServiceChannel.EndCall(String action, Object[] outs, IAsyncResult result)
bei System.ServiceModel.Channels.ServiceChannelProxy.TaskCreator.<>c__DisplayClass7_0`1.<CreateGenericTa sk>b__0(IAsyncResult asyncResult)
bei System.Threading.Tasks.TaskFactory`1.FromAsyncCoreLogic(IAsyncResult iar, Func`2 endFunction, Action`1 endAction, Task`1 promise, Boolean requiresSynchronization)

Any help / suggestions are highly welcome
Regards, Sascha

Edit: I've just been screening the other Express.log files uploaded here. What they have all in common (including mine) is the "Exception thrown by unobserved task" - just before the list of error messages becomes messy. Probably a starting point for investigation ... ?!?!

Installation of the map finished without error this morning but first the new card was not detected by Basecamp. After adding a link in the folder "C:\Users\All Users\Garmin\Maps" to the new installation folder (non default) it worked.
Why does the folder "C:\Users\All Users\Garmin\CoreService\Downloads" still contains the installation files (about 5G) ?
Why is it necessary that a simple installation program llke gamin express has an installation size of 280 M ?

Regards
Rainer

I do not get any errors about MD5 hashes but a message about "Could not determine where to install the map" seems to be the problem in my case. I have done a factory reset of the watch and installed Express on a clean Windows install with the same issue in all cases. The device is (apparently) detected ok and I have been able to install firmware updates to the watch using Express and maps to other devices. There is sufficient space for the map I am trying to install.

A relevant log is attached, the forum barfs with JSON errors if you try and post more than a line or two from it. It would be so much easier if we could just download the map directly and install it like with third party maps!

Correct, the MD5 error installing maps to the computer was resolved 9/27/2018 as another forum member already posted. If the error received is not an MD5, I recommend contacting Product Support for assistance.