How to fix error for Outlook Mobile Hybrid Modern Authentication (HMA) for SMTP email address

Question

Hi All, I am using the MicroSoft Outlook Mobile Hybrid Modern Authentication (HMA) testing tool to test my email but keep getting the following error: - Does anyone know what this errors means and if its related to firewall blocking URLs ? I have already added Office365 World Wide Services Jason object to allow all URL and domains on firewall so not sure what else is required ?

------Error----

Sending an empty Bearer token request to the on-premises Exchange ActiveSync (EAS) virtual directory: https://mail.XXXX.com/Microsoft-Server-ActiveSync. The on-premises Exchange ActiveSync virtual directory didn't return a valid response.  Test Steps Sending an empty Bearer token request to the on-premises Exchange ActiveSync (EAS) virtual directory: https://mail.XXXX.com/Microsoft-Server-ActiveSync.The on-premises Exchange ActiveSync (EAS) virtual directory didn't return a valid response.__Additional DetailsException details: Message: The underlying connection was closed: An unexpected error occurred on a receive. Type: System.Net.WebException Stack trace: at System.Net.HttpWebRequest.GetResponse() at Microsoft.M365.RCA.Services.RcaHttpRequest.GetResponse() Exception details: Message: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. Type: System.IO.IOException Stack trace: at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.FixedSizeReader.ReadPacket(Byte[] buffer, Int32 offset, Int32 count) at System.Net.Security._SslStream.StartFrameHeader(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.StartReading(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.ProcessRead(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.TlsStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.PooledStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.Connection.SyncRead(HttpWebRequest request, Boolean userRetrievedStream, Boolean probeRead) Exception details: Message: An existing connection was forcibly closed by the remote host Type: System.Net.Sockets.SocketException Stack trace: at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size)

Answer 1

Hi @Jay,

Welcome to post our Q&A forum!

The error message you received indicates that the on-premises Exchange ActiveSync (EAS) virtual directory did not return a valid response when you sent an empty Bearer token request to it. This could be due to a number of reasons, including a firewall blocking URLs or an issue with the EAS virtual directory itself.

You mentioned that you have already added the Office365 World Wide Services Jason object to allow all URLs and domains on the firewall. However, there may be other requirements that need to be met in order for the tool to work properly.

I would recommend checking the following:

• Ensure that the EAS virtual directory is configured correctly and is functioning properly.
• Verify that the firewall is not blocking any other URLs or domains that are required for the tool to function.
• Check that the tool is configured correctly and that all necessary settings have been entered correctly.

Similar thread please refer to: https://learn.microsoft.com/en-us/answers/questions/440903/test-oauthconnectivity-failt-from-on-premise-to-of

---

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".  Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.