This is a setting in our software. When it is selected, our software will look at all of the data in the selected area from scratch to see if it is the same on the other end of the sync. For example, if you selected 'Reread handheld data' in CompanionLink, this would tell CompanionLink to look at each record in the handheld again and resend it to your contact manager if the record in your contact manager differs in any way from the handheld. This is NOT recommended for use on a regular basis. It is intended for troubleshooting only.