Device emulator not connected - Waiting for all target devices to come online

[AlexEv]

Hi, I have installed to my Windows 10 absolutely fresh Android studio
Android Studio 4.1.1
Build #AI-201.8743.12.41.6953283, built on November 5, 2020
Runtime version: 1.8.0_242-release-1644-b01 amd64
VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
Windows 10 10.0
And a lot of various SDK, all is fresh releases.
Than I have downloaded test project (I select sunflower). And a couple of days I can not start it.
I learn a thousands various recipes, but still receive message - Waiting for all target devices to come online
I try to start Android studio as administrator, try to on/off various Window options (like enable/disable HyperV).
I try various options in device emulator, like wipe or cold start. But I have no changing. Device emulator not connected.
adb devices show me:
>List of devices attached
>emulator-5554 offline
In Android studio I see
>xx.xx * starting now at tcp:5037
>xx.xx * daemon started successfully
And Launching I still see :
>Waiting for all target devices to come online

What going wrong? Any ideas please...

 

[B. Diddy]

Welcome to Android Central! I moved this from the Android Apps forum to the Software Development forum since the former is intended for developers to promote their apps.