If you have configured you Skype for Business infrastructure to use UCS (Unified Contact Store) or if you have requested to get it enabled on Office 365 (yes, you do not have UCS activated by default on Office 365 and you need to open a SR to get it), you may face the following issue.
With Skype for Business client, you may have some notification
- When displaying the Configuration Information
MAPI Information;Your Outlook profile is not configured correctly. Contact your support team with this information.;MAPI unavailable;
EWS Information;;EWS Status OK; 
- Delegate functionality may be broken
If so, there is 2 plan: 1 simple, 1 a little bit more complex
Simple Plan – Deploy the July 5th 2016 fix
This is very simple, just download and deploy the fix from
- 32 bits SfB/Lync client: http://www.microsoft.com/downloads/details.aspx?FamilyId=cbd5a79a-95ad-4a09-9628-61ccd8292a63
- 64 bits SfB/Lync client: http://www.microsoft.com/downloads/details.aspx?FamilyId=ca5e2931-d89b-4cf2-af4c-6ce19261b47b
However this may not work, especially if you have Office 2013/Office 2016 Click To Run installation. The fix will not detect any product for which the fix must be applied.
You can try to force your Click To Run install to get updated but it seems the fix is not yet available neither (I did and the issue was not solved)
So, let’s take a look at the more complex action
More Complex – Registry fix
Launch the registry editor (regedit) and browse to the following key
HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Profiles and open your default profile
Then locate the subkey named 9375CFF0413111d3B88A00104B2A6676
Open the subkey and check each of the key until you found the one with your email address shown in the Account Name value
Take the value from the Service UID and then locate the subkey with the same value below the Profiles tree – like in this example the Service UID value is 980e871e9d8a8644b50ddd6c2c583715, the subkay to locate will be HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\Profiles\Outlook\980e871e9d8a8644b50ddd6c2c583715
Take the value from the 01023d0d binary value and repeat the same search
In this example, the value is 2c5e812328c4cb42bfbd2be3d360e7b3 so the subkey to search is HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\Profiles\Outlook\2c5e812328c4cb42bfbd2be3d360e7b3
There you need to create a new String value named 001e6603
Edit this new string value with the value of your mailbox LegacyDN – you can get the LegacyDN with the Test e-mail autoconfiguration from Outlook from the XML tab
Close your Sfb/Lync client and restart it. You should now get
UCS Connectivity State;Exchange connection Active;–;
MAPI Information;MAPI Status OK;MAPI Status OK;
