Solved — Unhandled Exception: PlatformException(channel-error, Unable to establish connection on channel., null, null)

How to fix Unable to establish connection on channel in Flutter

You’ve upgraded Flutter but not the packages. In the terminal enter

flutter pub outdated

Then upgrade the outdated packages one by one like this:

flutter upgrade outdated_package

After you’re finished:

flutter clean

and

flutter pub get

Your problem should now be solved.

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