you for reaching out on the community and telling us about your issue. I do apologize for the issue you're having. While I don't know exactly what the answer you're looking for I believe that there might be a couple of side effect from trying to block it most likely. I believe you'd likely lose the ability to download from EWC accounts as that is part of the connection to quickens servers to retrieve information. Another thing is it may also think you're not signed in as well and repeatedly ask to sign in.
I would recommend turning off the cloud overall rather than trying to block the connection as once it's turned off no information is stored on our side. If you have any other questions please let us know.
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