Today, I got this message when I tried to send an e-mail.

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Your Mail Outgoing blocked. Reason :Daily Mail Size Quota Exceeds Limit [Total Mail Size=102,400]

You can unblock yourself using this link:  https://mail.zoho.com/UnblockMe

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As you can check from the above message, my e-mail has about 10MB attachment. As far as I know, Zoho mail offers 20MB for attachments. How can I increase the size of attachments for my e-mail?

For understanding my situation, I'm using a Free & personal user option and I tried to send this email through my default Mail app in Mac OS X.