UPDATED: Feb 26 2018 (later that day)
This post is a follow up to how I got Xamarin Android Device Manager up and running on Windows. Please read the Xamarin Developer guide first which explains how to install and use the Xamarin Android Device Manager for Visual Studio on Windows (or for Mac). Please keep in mind that at the time of this post the Xamarin Android Device Manager is still in preview.
For me I’m running the latest version of Visual Studio 2017 (15.5.7) and I already had the Xamarin components installed and working. Up until now I wasn’t really using the Android emulators for any Xamarin development as I was more focused on iOS and Windows. However now I have a need to and so I decided to try out the new Xamarin Android Device manager. Why you might ask? Well as of Android SDK Tools version 26.0.1, Google has removed support for their UI-based AVD and SDK managers in favor of their new CLI (Command Line Interface) tools.
After having installed the latest version of the Xamarin Device Manager installer for Windows, I ran it from the Start menu with Administrator privileges like so:
And this is the error I get:
I ran through the troubleshooting section section and the issue is that I was missing the Android SDK (requires 26 or higher). Perhaps a one of the latest Visual Studio updates caused this issue because now none of the Android tooling like device or emulator are working. Perhaps installing the Xamarin Device Manager broke it, I’m not sure but it’s broken. The only way I was able to resolve this was to run the Visual Studio Installer and uninstalled the the Xamarin SDK Manager and re-install it. Here is what I did.
My Solution to Fixing Missing Android SDK
1. Run Visual Studio Installer and then click on the Modify button:
2. Now go to the Individual components tab and Remove Xamarin SDK Manager and then click on the Modify button to apply the changes. Take notice of the amount of disk space that will be freed up. For me it was 113 MB.
3. Now do steps 1 and 2 again but this time add back the Xamarin SDK Manager and then notice the amount of disk space required for these changes…for me it was 1.4 GB, obviously something screwed up and I was missing a great deal. Now apply the changes by clicking on the Modify button.
Now when you run the Xamarin Android Device Manager from the start menu (with administrator rights) it should load up as expected. Now if you are like me and don’t have the latest Android SDK Tools, then you are then presented with the following dialog prompting you to download them from the Xamarin Android SDKs and Tools manager:
When the Xamarin Android SDK and Tools manager opens, review the SDK platforms you want installed and then click over to the Tools tab:
In the Tools tab, expand the Android SDK Tools selection and change the selected tooling to the current version which is 26.1.1 and then click on the Apply Changes button. If you’re just changing the Android SDK Tools, this should only take a couple min at most to apply. Once it’s done close down the Android SDKs and Tools manager.
Now go back to Visual Studio (re-run if you have it running already) and run the Android Emulator Manager from the Tools – > Android menu.
You will now be presented with the new Android Devices manager. When you first launch the Android Device Manager, it presents a screen that displays all currently configured virtual devices. For each device, the Name, Operating System (Android API Level), CPU, Memory size, and screen resolution are displayed:
I then went on and added a new option for Android Oreo and when I tried to run it I got another error:
Now it looks like I need to install another tool, Intel’s HAXM which requires Hyper-V be disabled.
Summary
What seemed like a quick and easy update has turned into quite the adventure. It’s 2018…why can’t this be more simple!
Enjoy!
References
Channel 9 | The Xamarin Show: Snack Pack | The New Xamarin Android Device Manager
How to setup and create Android virtual devices using Xamarin Android Device Manager
The Flying Maverick 
Hi Callon! Thanks for your post. This is a *preview/alpha* feature and we are aware of the issues and have fixed all of them for the upcoming release. We shipped it early with a few known issues specifically to get feedback from the community to develop a better stable version. We appreciate your feedback and hope you give the next update a try – it’ll be included by default in your Xamarin upgrade and should just work out of the box.
This post ultimately fixed the AVD Manager problem for me. I already had installed v26, but it refused to start.
Reinstalling Xamarin as a whole did not change things.
Downgrading to v25 and and reinstalling v26 after that actually did the trick! 🙂
this emulator is not compatible for windows 10 home. so please dont waste ur time. i wasted my half day in figuring out this.
https://social.msdn.microsoft.com/Forums/vstudio/en-US/1cfd8e2c-3e9b-4269-99dd-b28f53e85c46/cannot-install-microsoft-visual-studio-emulator-for-android-on-windows-10-10230-meanwhile-cannot?forum=vssetup
Hi, In visual studio 2019 installer “XAMARIN SDK MANAGER” component is not available. then what should I do now?
Google redirected me here to your website trying to find a solution, to almost the same Issue, despite I was trying to run it using my mobile instead of virtual device,
Despite the error Building , I was able to run the App sometimes,
Well, Maybe I am too late but I found what was the issue,
A problem happened with My PC made me reset my BIOS settings including restoring the Intel Hyper-V technology to enable,
Everything is working fine after disabling the Hyper-V Technology,
I hope my comment being helpful to others that are seeking a solution for their Xamarin Android SDK errors.
Have a great day everyone and enjoy coding 🙂