To ensure secure network connections with the Minecraft: Education Edition services, the security protocols used by Minecraft: Education Edition are getting updated on June 29, 2021. The updates may affect Windows 7 users.
Who is affected
In order to not be affected by the update, make sure your Windows 7 device has all the recommended updates installed. If your device is not up-to-date, you will see the following message when you launch Minecraft: Education Edition:
We were unable to sign you in. Please make sure you are signing in with your school or organizational account and try again.
Screenshot of message
Update your device
To update your device and be able to log in to Minecraft: Education Edition, follow the processes provided in the Update to enable TLS 1.1 and TLS 1.2 as default secure protocols in WinHTTP in Windows article.