If you experience an issue with the WebDataHub add-on, for example the add-on doesn't work correctly, it is a blank white screen, or there is a payment/account issue, it could be because you're signed in to multiple Google accounts. This is a known issue with Google Accounts and Google Apps. To fix the issue, sign out of your other Google accounts in your browser, or sign in to 1 Google account in a different browser, then try again.
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