I could be wrong here because I don't know much about BES, but I am pretty sure you can have BES and BIS setup at the same time. You will want to login to your carriers BIS site and delete it from there and resend your service books. However, this may all be different since you are using BES and it is a work berry.
Question for the others too... is it possible for him to just delete the service book on the berry for his Yahoo! account, instead of logging into the BIS site? I know that if he resent his service books at a later date, it would add it again.
Yes, you can have bes and bis email on the same device. I don't believe you can separate them. I set up different colors for my bis and bes accounts, but you don't see the colors until you open the message.
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