The error below is printed in the flutter console (flutter\flutter_console.bat) but VS code and Android studio console (flutter\bin\flutter.bat) do nothing (just waiting for resources), so users who have Powershell below 5.0 don't know that they need to upgrade. This is likely to affect those on Windows 7

It happens after running one of the following commands:

flutter upgrade
flutter update
flutter doctor

Environment variables are set up as follows:

C:\Windows\System32;
E:\flutter\flutter\bin;
E:\git\Git\bin;

Checking Dart SDK version...
The term 'Unblock-File' is not recognized as the name of a cmdlet, function, sc
ript file, or operable program. Check the spelling of the name, or if a path wa
s included, verify that the path is correct and try again.
At line:1 char:13

• Unblock-File <<<< -Path 'E:\flutter\flutter/bin/internal/update_dart_sdk.ps1
  '; & 'E:\flutter\flutter/bin/internal/update_dart_sdk.ps1'
  • CategoryInfo : ObjectNotFound: (Unblock-File:String) [], Comman
    dNotFoundException
  • FullyQualifiedErrorId : CommandNotFoundException

Flutter requires PowerShell 5.0 or newer.