If the installation of the Directory Synchronization tool fails, check the Event Viewer. Installation may fail if the Microsoft Online Service SignÂIn Assistant is already installed on the system.
If you need to uninstall the Directory Synchronization tool, log off and then login.
If the Directory Synchronization tool is slow, increase RAM of the server.
If the active profile authentication fails for Microsoft Exchange (Outlook) clients, verify that the necessary DNS records have been added to your DNS.
Manually install Microsoft Online Services Sign-In Assistant, if its installation fails after installing Microsoft Office Professional Plus with this message:
"The Microsoft Online Services Sign In Assistant has experience an error. The error must be resolved before your subscription for this product can be verified. To retry subscription verification, first resolve error message 800704DD or try to manually install the Microsoft Online Services Sign In Assistant...."
After installation is complete, relaunch the service to verify your Office 365 license.
If single sign-on fails, ensure that the ImmutableID and the User Principal Name (UPN) matches the Office 365 user. To get Office 365 user details, log in to using Powershell and execute the following command:
Get-MsolUser -UserPrincipalName user1@namtest.com | fl *
If you receive an error stating that the user does not have license to use Office365, Log in to Office 365 as an administrator and assign required service licenses to the user.
After successfully authenticating to the Office 365 client, if you attempt to log in to the Lync client by using an incorrect username and password, the Lync client uses the details from the previous successful session and tries to get a token from Access Manager. This results in an unending loop.
To resolve this issue, in the Lync client user interface, select the Delete my sign-in info option and log in again.