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 j528868: I had the same issue when trying to set up my UPS account with the access denied error message. I am not sure if this will work for you, but the way that I circumvented the issue was expanding the window and instead of using the log in that appears at the center of the pop up, I went to the log in option at the top right and logged in as I normally would to access my UPS account. For some reason, this was successful to at least connect my UPS account with this new shipping manager.