Overview
You have just signed up for a Nebula Synchronizer account, and you are using a (hosted) Exchange account but for some reason, the authentication fails on step 2 during the Nebula Wizard.
How to
This happens when there is a misconfiguration regarding the Autodiscovery. In some special situations (hosted Exchange), Autodiscovery might not be available (always ask your (local) IT first).
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To get it to work we need the following information:
1) Exchange Web Services (EWS) URL
This is needed to communicate with the mailboxes (KB article).
2) Offline Address Book (OAB) URL
This is needed to link the SuperOffice users with the Exchange/Outlook users (KB article).
3) Local Domain name
This is needed for authentication on the Exchange environment (KB article).
4) Local Windows/domain Username
This is needed for authentication on the Exchange environment (KB article).