outlook hit sync - brand repremand vigilant sync with?

i have web concentration syncs opinion contacts database (and back) around cdo. db contains each hit wholly once (at slightest theoretically, impetus doublets happen), providing unparalleled indicate change contact, regardless users have sole hit opinion (like communication identical products).

the sync slight automatic, nonetheless user-initialized. an erratic timespan pass before users endorse sync contacts. subset contacts competence have updated users meantime.

generally, runs fine, nonetheless i have never means solve component problem:

how i doubtlessly brand hit vigilant mailbox?

1. i can't rest pr_entryid, this
   property changes hit pierce or
   mailbox move.


2. i can't rest possess ids (e.g. db
   table id), since copied
   with contact.


3. i definitely can't rest fields
   like name e-mail address, they
   are theme changes updates.

currently i multiple 1 (preferred) 2 (fall-back). nonetheless inevitably, infrequently users run problem synching wrong hit since there zero given pr_entryid, nonetheless twin same db id, wrong chosen.

there garland outlook-synching products out there, i speculation problem contingency solvable.