Setting it up is very simple. You only need to run the application, go to Menu>Settings and enter your email address and the password of your Exchange email account. The advanced setup is available, if you want to change or manually configure the Exchange Web services address.
Synchronization works in a straightforward and direct way: ContactsSync connects to your Exchange server and loads your contacts right into your phone. To start loading your contacts from Exchange, run the application and click on the "Load contacts" button.
ContactsSync works perfectly for updating data in your G1 phone address book. If a record has been changed at your Exchange server, the record on your G1 phone will get updated during the next synchronization.