Hello @Alan2,
Thank you for reaching out to the Quicken Community with this question.
What exactly is the issue that you are experiencing with Coinbase? Are you receiving any error codes or messages? Have you attempted to link your account(s) using the instance located in the screenshot below?
I look forward to your response!
Thank you for providing more information, though I do apologize for the delay in response.
This error occurs when your financial institution has added either a new page to its website or a pop-up window that requires your action to bypass it. You may follow this link to access a FAQ that discusses the CC-508 error message in more detail. It is recommended to save a backup before proceeding with troubleshooting steps (just in case).
I hope this helps!