Ive owned 7510/20 and now a 7100i. I never reallypaid much attention but when the option of deleting an email reads 'handheld only' or 'mailbox and handheld' i usually select mailbox and handheld. The emails have always remained in my mailbox. They show that they have been opened but the phone will not delete it using the blackberry. hotmail and yahoo, not using bes... is that the diff?