troubleshooting Question

OAB NTLM authentication failing, all settings are set to MS recomendations

Avatar of awilderbeast
awilderbeastFlag for United Kingdom of Great Britain and Northern Ireland asked on
ExchangeOutlookMicrosoft IIS Web Server
17 Comments1 Solution985 ViewsLast Modified:
Hi All,

Some users are getting OAB prompts, ive checked the logs and have attached the event screen.
I have set OAB authentication permissions as per MS recommendations
and the OAB permissiosn as per

It may be worth noting that our primary email addresses are, and our actual domain name is, could it be possible that is being sent as part as the username for ntlm auth? can we make it do domain\username for OAB? that possible?


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