Hello @sverba
Thank you for reaching out on the community and telling us about your issue. I do apologize for the issue you're having. Currently we are experiencing issues with BoA which could be related to the issue you're having as they're similar issues and in the same time frame. I'd recommend following the article down below for more information and any updates as well.
https://community.quicken.com/discussion/7891383/new-4-2-21-bank-of-america-returns-cc-501-error
Thanks,
Quicken Francisco