Test-OutlookWebServices PowerShell command fails

Are you running the command on exchange server? Also can you post the complete error or screenshot?

Yes, ran the command on our exchange server.  The complete error is...

WARNING: An unexpected error has occurred and a Watson dump is being generated: Object reference not set to an instance
 of an object.
Object reference not set to an instance of an object.
    + CategoryInfo          : NotSpecified: (:) [Test-OutlookWebServices], NullReferenceException
    + FullyQualifiedErrorId : System.NullReferenceException,Microsoft.Exchange.Management.SystemConfigurationTasks.Tes
   tOutlookWebServicesTask

Does it gives error for all users?

The error sounds to me like something may not be correctly installed or configured.  Do you get the same error is you try from another management console?   Is there a corresponding error in the event log?   Where does the id reside on-prem or O365?

The user is on O365.  There is a remote mailbox entry in the Mail Contact section of EMC so I thought that wold suffice.  Maybe I need to run this in the Azure AD powershell?  I tried that and I get the error that the command is not recognized as the name of a cmdlet.

I don't think the command Test-OutlookWebServices applies to exchange online.. Check Applies to: section from the references..

http://technet.microsoft.com/en-us/library/bb124509%28v=exchg.150%29.aspx
http://technet.microsoft.com/en-us/library/bb124805%28v=exchg.141%29.aspx

Does the command work well for your local exchange mailboxes?

We are in hybrid mode and I'm trying to test AutoDiscovery which is done from our Exchange 2010 SP3 server.  Microsoft has website for testing AutoDiscovery, but you have to provide the user's password.  I can test it for myself, but not other users.  Does anyone know another way to test AutoDiscover?