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For a free backup program you wont get too many features but as you asking only for 30 GB i think you can find a lot but i recommend to use Dmailer http://www.dmailer.com/dmailer-backup.html they also offer online storage for backups if you need any. The software is free and after my oppinion is the best software i ever used and found because has a lot of other features than all other free softwares. Take care