Android Emulator gives error: Cold Boot: Snapshot doesn't exist

I too faced this issue for a while and recently resolved it. Through reading other SO posts it definitely seems to be related to the snapshot that the Emulator is trying to boot from - as eluded to by @Raimo's answer. Although I don't fully understand the cause for why this is happening (it happened to all of the AVDs I had saved) I've resolved it by configuring my AVD to perform a "cold boot" instead of a "quick boot" whenever I launch it. This solves the "Snapshot doesn't exist" message & the emulator boots as expected, allowing you to run and test your application.

Steps to fix the issue:

1. Open the Android Virtual Device Manager (Tools -> AVD Manager)
2. Select the Virtual Device you'd like to use & click "Edit this AVD" (the Pencil icon)
3. The "Virtual Device Configuration" window should now be open. Click the "Show Advanced Settings" button at the bottom of the window and scroll to the "Emulated Performance" section
4. You'll see an option called "Boot option" which is typically set to "Quick Boot" by default - switch this to "Cold boot" and click "Finish".

Start the Virtual Device now (close it if you previously had it running whilst making these changes so that they take effect). The "Snapshot doesn't exist" message won't appear and your emulator will start as expected.

The only downside to this option is that the state of the device when you last used it won't be stored i.e. your apps you previously had open.

Quick Boot is not reliable when software rendering is enabled. If Quick Boot does not work, click Edit this AVD from the AVD Manager and change Graphics from either Automatic or Software to Hardware.

Source: https://developer.android.com/studio/run/emulator.html#quickboot-troubleshooting

Today I have tried all methods, all stucks me.

1. I don't launch Android SDK Manager GUI, using android command is deprecated.
2. Android Studio does not open for disabling Cold Boot.

At last I found a solution, using CLI command:

emulator -avd YOUR_AVD_DEVICE_NAME -no-snapshot-save