Hello @bthodla
Thank you for reaching out on the community and telling us about your issue. When asking for a sign in is it asking for a quicken ID or intuit ID? Ideally it would be asking for a quicken ID as Intuit ID's are no longer in use. That generally is the big problem when we're unable to sign in on older programs.
There's also another support article that has an issue very similar to what you're experiencing. There's quite a few recommendations for fixes that could get you back up and running. I'll link that down below.
https://community.quicken.com/discussion/7878356/quicken-2016-has-suddenly-stopped-working#latest
Once you get a chance to answer the original questions please let us know!
Thanks,
Quicken Francisco