When you replaced the 890, you should have just used the Replace Remote option in the Harmony software. Are these 890s the 890 Pro by chance? with the 890 Pro, you could have up to 6 890 Pros in one account. With the 890 Pro, unless you permantly deleated the remote from your account, by naming the new remote "New 890", you never deleted the old remote from yopur account, and everytime you do an update it will look for the opd 890 to update it and the extender.