Web API Authorization Code Flow Error

[killani64]

I'm implementing a simple application to generate some playlist for a user based on some provided data. However, I can't seem to get authorized, even though I've followed to procedures as far as I can tell.

This is the request URL I'm generating:

"https://accounts.spotify.com/authorize?response_type=code&client_id=*MyClientId*&scope=playlist-modify-public&redirect_uri=localhost:8999%2Fcallback"

I have registered the redirect uri exactly like that in my application (replacing the %2F with a slash). I'm getting an amazingly vague "Oops, something went wrong" error message with a 500 status code after putting in my authentication details. Can anyone tell me what I'm doing wrong?

[killani64]

I seem to have fixed it by adding "http://" in front of the URI, both in the dashboard and in the request.