Hello @Frank002,
Thank you for reaching out to the Quicken Community with this issue.
Due to the nature of this error message, we recommend reaching out to Quicken Support directly as an escalation may be necessary. The Quicken Support phone number can be found through this link here. Phone support is available from 5:00 am PT to 5:00 pm PT, Monday through Friday.
I apologize that we could not be of more assistance.
Based on all the discussions here in the Community, that error message, often accompanied by error code CC-501, is something that requires escalation to Quicken Tier 2 Support personnel. They need to research the problem and try to figure out the cause. Sometimes it can be resolved by fixing something in the user's profile on the server. Sometimes it needs more escalation to the download service provider, Intuit, and a more global fix to be applied. All this depends on in depth research into the error.
So, everybody please contact Support, report this Online Banking issue and request escalation and further research.