The URL you provided is invalid. The URL may have been broken across multiple lines in your email client, like this:
https://dlc.dlib.indiana.edu/dlc/register?token=ABCDEFGHIJK
LMNOP
If so, copy and paste the entire URL directly into your browser's address bar, rather than simply clicking on the link. The address bar should then contain something like:
https://dlc.dlib.indiana.edu/dlc/register?token=ABCDEFGHIJKLMNOP