Problem and Fix: The app did'nt start(HRESULT:0x8027025B)

 The fix was to use the right combination of Target min version.

I faced quite a bit of downtime due to the wrong choice of the target version working with UWP Projects. Web search to find a cure sent me searching for answers I could not find.

I am using Microsoft Visual Studio Community 2017 Version 15.8.1. The Dell Laptop is running Evaluation copy of Build 17733.rs5_release(18083-1525). [This OS has a problem in that when you shutdown and restart the OS, it will reinstall the OS afresh wiping out some of the folders; saved passwords; saved items in Microsoft Edge. Visual Studio also gets reset.].

Now coming back to the right Target version for working with UWP projects, there are three options for the Target version shown in this image.

RightTargetVersion_0

Of the three options only one of them allows the Design editor in Visual Studio come up without this error - The app did'nt start(HRESULT:0x8027025B). This is the only one that works:

Windows 10 Creators Update (10.0; Build 15063).

Regarding the choices for the Min Version, Build 15086 and Build 15063 works without any changes, just the Solution refreshes.

RightTargetVersion_2

However, if you were to choose Build 14393.0 you need to install the required SDK.

RightTargetVersion_1

These findings are summarized in the next image.

RightTargetVersion_3

Regarding UWP Support for .NET Standard 2.0

Mostly I am looking at what I have to verify that they are enough for developing latest UWP Projects. The main feature that .NET 2.0 Standard brings about is the access for about 20000 APIs.

So what are the requirements?

You need to have Visual Studio 2017 v15.4. According to my previous post this was installed sometime ago (1, 2).

VS2017Comm_About

The other requirement is that you should be running and targeting correct version of  Windows 10 Fall Creators Update.

These requirements are the baseline for UWP tools.

I am using the free Visual Studio 2017 Version and in my project properties I find that I can choose couple of options for the Min version for Windows 10 Fall creators Update as shown.

VS2017Comm_MinTarget 

Note however, that when you try to change the Min target version you will need to heed to the following message:

VS2017Comm_MinTargetx2

When I changed the Min version to one suggested, the Microsoft.Net.Native.Complier 2.0 was installed after which the Hello World Project was restored.

VS2017Comm_MinTarget 3

UWP Reference properties after the change are as shown:

VS2017Comm_MinTarget 4

Looks like I am well set.