Juniper Allegro CE Owner's Manual page 146

Unresolved Files through File Synchronization
It is very important to note that the synchronize files option always
replaces all old files with the most recent file. If you have saved a
document on the Allegro in the My Documents folder, it automatically
transferrs to the Allegro My Documents synchronization folder on the
desktop PC with the same name.
After disconnecting communication between the Allegro and desktop
PC, the synchronized file can be altered. When reconnecting the
Allegro to the desktop PC after, ActiveSync's file synchronization will
replace the unaltered document with the master updated file.
The synchronization proces stops when both documents, the one on
the Allegro and the one on the desktop PC, are altered and ActiveSync
is unsure which one is the master document. The following screen
appears:
Page 4-86 Windows CE