Error on line 1, column 1 of pubspec.lock: Unexpected character

Question

I tried to run flutter pub get and I got this error:

Error on line 1, column 1 of pubspec.lock: Unexpected character
╷

1 │
│ ^

  ╵
pub upgrade failed (65;   ╵)

Answer 1

The file pubspec.lock is a generated file, so you can delete it and then regenerate it.

Delete pubspec.lock.

Run the following command:

flutter pub get

or

flutter pub upgrade

Notes on pub upgrade (you could probably skip the delete step).

Answer 2

Delete the file at flutter/packages/flutter_tools/pubspec.lock then try flutter pub upgrade again.

You may have interrupted the upgrade process before it finished hence the file became invalid.