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VS xamarin phone emulator wont turn on

I am making an android application on xamarin VS 2019.
I tried using different VS emulators. When I debug, the phone loads and I can rotate it but when I try to turn it on it does not work. It says that System UI won't turn on and at other times it says that the process failed. I cannot figure out why, I did exactly the same as the tutorial.

Android forms previewer renderer instead of the usual preview

I just created a mobile app with xamarin.forms and I wanted to start, by making the navigation of the application. Upon creating a content page the previewer ends up not showing anything, apart from a text saying:
Android forms previewer renderer instead of the usual preview.
I'm using Visual Studio 2019 and I have the nugets all updated.

After trying a bunch of stuff I ended up creating like 5 or more projects and somehow the previewer on the last on is working but on the other ones it just ain't.

project built succesfull in Unity and installed on android but doesn't run properly

I created an app in Unity where you get a start screen with some GUI elements: a top bar with some title graphics and a scrollView with buttons that load dynamically using c# and xml that allow me to active canvases depending on the pressed button... this all works perfectly when I run it on pc but when I try to install it on android, it only shows the "Made with Unity" animation and loads the top bar and the background.. I just can't get any gamelogic to run..
I even forced the first level to run, and it switches canvas but nothing else, no sprites loaded into the GUI images, no listviews being populated, nothing..
I then tried to load a canvas that should be able to search for levels/chapters with an inputfield and then display all chapters that contain that text.. I can select the inputfield, the onscreen keyboard appears and I can type text, but again, the list isn't being populated..
I did have a lot of trouble getting the app to build (commandInvocationFailure, ..) and searched the web for every error I got and kept getting new errors untill I found a "sweet spot":
Unity 5.6
SDK that came with newest Android Studio
Downgraded tools in SDK to version 25.2.5
Had to copy zipalign.jar from build-tools to tools
downgraded JDK from 9.1 to 8.1
install location "automatic"
this allowed me to build my app but it's extremely fragile, one wrong setting and it won't build..
I'm trying to run the app on a Samsung Galaxy Tab4 (Android 5.1 Lollipop) I installed the proper API with SDK Manager but when I set the API level in Unity I can only select "highest installed" or it won't build. I tried installing on a Samsung Galaxy Tab A (Android Nougat) but there I get a "Not Installed" message.. (third party sources is checked)
The build itself is quite large (1.7gig but has over 3000images and sounds which I downsampled so all resources are around 500MB)
(the entire app is made out of GUI elements)
anyone who encountered this problem or can shed some light on what I'm doing wrong?

Found the answer: app depends heavily on xml and adressing an xml file on android is different than on a pc.. so app worked but couldn't find the xml so no data was loaded..

Can't change the icon of a console app in Visual Studio Community Edition

I am making a console app in using C# .NET version 4.5 in Visual Studio.
Whenever I try to add a 32x32 or 256x256 icon file (converted from 24-bit bitmap using MS paint) it says "C:\Users\ipass\Desktop\icon32.ico is not a valid icon file." I have tried using different icons, switching from a console app to a Windows app type, restarting my computer, moving the icon to a different directory, changing the icon of a different console app, and using SharpDevelop instead of Visual Studio. Nothing seems to be working.
Let me know if you need more info. I am attempting to change the icon by Right clicking the project in solution explorer>clicking 'Properties'>navigating to 'Application'>and clicking browse under 'Icon and Manifest'.

If so it is probably giving the error because the actual file type is not what Visual Studio expects a .ico to be (the size of or information in the file header, for example). Also, the image may have to be a certain size, like 64x64 pixels.
You could try an online converter to convert an image file into a .ico file
http://www.convertico.com/
http://www.icoconverter.com/
The wikipedia page for .ico has more information that might help - http://en.wikipedia.org/wiki/ICO_(file_format)

How do I have a sample image available in WP7 emulator when my project runs?

I have a Windows Phone project compiled with 7.1 SDK. The application processes image files and I'd like to have a sample image file with the project so that when the project runs in the emulator and the user asks the application to open an image from the photo gallery (using PhotoChooserTask) my sample image somehow magically appears in the gallery and the user can select it.
I've seen this question and I'm not completely sure it's about my scenario. That question OP wants to test his custom image. I want my custom image included into the project and then automagically appear in the emulator when someone gets my project from GitHub and opens it in Visual Studio and just runs it.
Is it possible to have a sample image included into WP 7.1 emulator when the project is being run?

I wrote a blog post that explains how to have sample images in the emulator: http://www.softwareisinthedetails.com/2012/11/add-test-images-on-windows-phone-emulator.html