1.) If you do not log in for a continuous period of 30 days, then further incoming emails will be blocked.
2.)Further, you need to log in at least once in 45 days. If you do not, all emails in your Inbox from the 46th day onwards, will be deleted.
3.)Also, if you do not log in even once for a continuous period of 90 days, your account will become permanently inactive (deleted). Once this happens you will not be able to log in or use your Rediffmail account at all.
4.) Exception to policies 1, 2 & 3 above: If you have subscribed for send SMS, POP3 access, Rediffmail Plus, Rediffmail Mobile or any other paid Rediffmail service; however, your account will remain active for the entire period of the subscription, i.e., even if you do not log in.
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There is no specific option to delete your Rediff Account. However, most of the e-mail service providers do come with a time-lapse period of about 90 days, following which your e-mail services get automatically de-activated if inactive. You can try not accessing it for about three months. You may however receive a 're-activation' e-mail after 90 days if incase you choose to start it again.