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I have been using Xamarin Remote iOS Simulator for Windows with Visual Studio Professional edition. Upon updating to the latest version of Xamarin for Visual Studio, I no longer see the option for remote simulator as mentioned here
The iOS Simulator is available for Visual Studio enterprise now.
The preview was available for everyone earlier
One way to solve this problems is to downgrade your xamarin. You can be using the 4.2 - Sep 26, 2016 version and the checkbutton still there.
You can do this using this tutorial: https://kb.xamarin.com/customer/portal/articles/1699777-how-do-i-downgrade-to-an-older-version-of-xamarin-
I fixed it with screen sharing using VNC Viewer. It is not for everyone, but I often had to go to mac and back to PC, it is more comfortable for me now. But I am considering to develop native apps, there is so many issues with xamarin and it wastes a lot of time again and again