DaemonUmbra

It's looking like your Minecraft jar isn't original. Delete your 1.14.4 jar (C:\Users\Blake\AppData\Roaming\.minecraft\versions\1.14.4\1.14.4.jar) and run the installer again.

Did you try the same solution? If not please make your own thread

If you have an issue please make your own thread with logs.

1.8 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

Please provide debug.log from both server and client

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

This is a 1.12.2 log, which version are you playing?

Note that because of the way Twitch works, downloading Forge manually will not fix the issue unless you launch the Twitch pack without using Twitch. (See the video in my signature)

The solution is complaining to BT and turning off their advanced security features

What do you mean?

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

What do you mean by this?

Threads merged. Can't help but notice this log you posted STILL shows a version of Java that is not the one I linked...

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

Make sure the drivers for it are installed correctly, beyond that I'm not sure there's anything that can be done

Are you a BT customer? If so:

What do you have for graphics hardware?

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

If you're seeing the message I'm thinking of that shouldn't be stopping you from downloading Forge