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You need to set up the email as IMAP instead of POP. POP email downloads to the device it is received on and is removed from the server. IMAP stays on the sever, so it can be viewed from multiple computers, until you delete it or move it from the server to your hard drive. Delete the email acct from your iPod, change it from POP to IMAP on your computer, and then set up your email again on the Ipod. Google how to set up IMAP if you have any problems.