itunes for windows "sign in" doesn't get a response

I cannot get a prompt to sign into my Apple account within iTunes on my old PC. I was previously signed in and signed out after installing Apple Music on my Android phone. I want to sign into my iTunes account on my PC so I can sych the music there with Apple Music (my phone is currently showing all the music on my MacBook, which is a subset of my larger library on my old PC).

I just need to sign within iTunes for Windows 7. Yes, my iTunes is up to date, as is Windows (as up to date as it can be with Windows 7).

Thank you.