About synchronization conflicts
A synchronization conflict occurs when you change the same email message or organizer data item on your BlackBerry® device and in the email application on your computer.
If you reconcile your email messages using wireless email reconciliation, on your device, you can set whether the email messages on your device or the email messages on your computer take precedence when an email reconciliation conflict occurs.
If you synchronize your organizer data using wireless data synchronization, the organizer data on your computer takes precedence over the organizer data on your device when a data synchronization conflict occurs.
Research In Motion recommends that you regularly create and save a backup file on your computer, especially before you update any software. Maintaining a current backup file on your computer might allow you to recover device data if your device is lost, stolen, or corrupted by an unforeseen issue.