Installing, configuring, and running the GroupWise/Exchange coexistence solution yourself works best in a scenario where you do not need to retain previously synced information. This includes the following situations:
You are currently syncing users between the two systems, but you are not satisfied with the solution you are using.
In this case, you are not concerned with retaining previously synced information. You are willing to delete the previously synced users and begin anew.
If you choose this approach, you lose the following:
Previously synced users
System and personal group memberships for previously synced users
The ability for users to reply to existing messages that originated outside their respective systems
This means that Exchange users will not be able to reply to existing messages from GroupWise users, and GroupWise users will not be able to reply to existing messages from Exchange users.
Correct email addresses for Exchange users in GroupWise personal address books
GroupWise users might encounter missing entries or duplicate entries for Exchange users in their personal address books, including the Frequent Contacts address book. When they select Exchange users from the GroupWise Address Book, email addresses are correct.
You are currently syncing users between the two systems, and you are satisfied with the sync solution you are using.
In this case, you would retain your existing sync solution and only use the GroupWise Free/Busy Service functionality of the GroupWise/Exchange coexistence solution. You would not need to implement the GroupWise/Exchange Address Book Synchronization functionality. However, you would need to determine how to populate the free/busy URL attribute for the synced users. This attribute displays in the Free/Busy field on the Details tab of a contact in a GroupWise address book. You could populate the attribute by:
Manually adding the free/busy URL to Exchange users in the GroupWise Admin console. Right-click each External User object that represents an Exchange user, click Properties > GroupWise > Internet Free/Busy Search, then specify the free/busy search URL for the Exchange user.
Configure your existing sync solution to populate this attribute on External User objects.