Starting from the beguinning
Instead of signing in to your primary account
Sign in the same way but using your subaccount info
Once your in go to Check Email
To bulk delete Email
Thanks to :
Re: How delete over 20,000 old emails messages easily?
03-23-2012 10:13 PM
To delete all of your messages from your inbox, go to the settings tab, and then go down to "Number of messages per page" and set it to "No limit". Hit "Save" at the top and then hit OK when it asks you to refresh your browser. Then in your inbox, check the box that is to the left of "Sender" and hit delete. It will take a long time if you have that many messages, but it'll get done. Cheers!
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