How do I fix this issue. ITunes Library.itl cannot be read because it was created by a newer version of iTunes?

It's very easy.

Go to C:\Users\(your username)\Music\iTunes and rename the file "iTunes Library.itl" to "iTunes Library.OLD"

Open iTunes, go to Help --> Check For Update, download & install the most recent upgrade. Once complete it will usually requires a computer restart. If not, you must close iTunes for the next step to work due to "File In Use" issues.

Go back to C:\Users\(your username)\Music\iTunes and rename newly-created "iTunes Library.itl" to "iTunes Library.NEW" (or just delete that file). Then rename your old file "iTunes Library.OLD" back to "iTunes Library.itl".

When you next open Itunes your old library will be accessable.