Exchange 2010:

SSLOffloading: False
ExternalHostname: mail.company.com
Clientauthenticationmethod basic
IISAuthenticationMethods: {Basic, Ntlm}

Exchange 2013:

SSLOffloading: False
ExternalHostname: mail.company.com
InternalHostname: mail.company.com
ExternalClientAuthenticationMethod: Basic
InternalClientAuthenticationMethod: Basic
IISAuthenticationMethods: {Basic, Ntlm}
ExternalClientsRequireSsl: True
InternalClientsRequireSll: True

Now there was a following problem. Users whose mail boxes are on Exchange 2010 when they start Outlook 2010/2013 requests the credential. If to enter login and the password that the user it is connected to Exchange. But such occurs at each start Outlook.

• Edited by Anton Moshkovskiy Friday, May 29, 2015 3:56 PM

Exchange 2010:

SSLOffloading: False
ExternalHostname: mail.company.com
Clientauthenticationmethod basic
IISAuthenticationMethods: {Basic, Ntlm}

Exchange 2013:

SSLOffloading: False
ExternalHostname: mail.company.com
InternalHostname: mail.company.com
ExternalClientAuthenticationMethod: Basic
InternalClientAuthenticationMethod: Basic
IISAuthenticationMethods: {Basic, Ntlm}
ExternalClientsRequireSsl: True
InternalClientsRequireSll: True

Now there was a following problem. Users whose mail boxes are on Exchange 2010 when they start Outlook 2010/2013 requests the credential. If to enter login and the password that the user it is connected to Exchange. But such occurs at each start Outlook.

Your client authentication is set to basic, so that probably explains the prompt if they are going through the 2013 CAS. I would se