exchange MAPI error HttpStatusCode: 401 Failure LID: 47372

Question

Hi all,

On newly installed on prem exchange 2019 i have problem that some times (not all the time) outlook 2019 starts constantly asking password, when i type in correct password after 3 s. it ask again and again.

Also Microsoft Remote Connectivity Analyzer some times gives 401 error for MAPI connectivity,

The logs is below.

Testing the MAPI Address Book endpoint on the Exchange server.

An error occurred while testing the address book endpoint.

 

Test Steps

 

Testing the address book "Check Name" operation for user ***@domain.com against server mail.domain.com.

An error occurred while attempting to resolve the name.

 

Additional Details

A protocol layer error occured. HttpStatusCode: 401

Failure LID: 47372

Failure Information:

REQUEST [2024-03-16T17:50:43.5572826Z] [ResolvedIPs: ...]

POST /mapi/nspi/?mailboxId=dedaeee9-c194-4869-a62a-f7d5ec4f360b@ domain.com HTTP/1.1 Content-Type: application/octet-stream

User-Agent: MapiHttpClient X-RequestId: 84d63ec9-79eb-4fdd-837b-bda52d6e2965:1

X-ClientInfo: 6ceead99-899e-41ce-9cee-ecb779c5b4b9:1

client-request-id: 5d59a05e-a548-4d22-86fa-8dad6a246911

X-ClientApplication: MapiHttpClient/15.20.7002.0

X-RequestType: Bind Authorization: Negotiate [truncated]

Host: mail.domain.com

Content-Length: 45

 

--- REQUEST BODY [+0.330] --- ..[BODY SIZE: 45]

--- REQUEST SENT [+0.330] ---

 

RESPONSE [+0.709]

HTTP/1.1 401 Unauthorized

request-id: c62cb78d-6116-4910-a6c7-f161fabe9104

X-OWA-Version: 15.2.1118.7 X-FailureContext:

FrontEnd;401;VW5hdXRob3JpemVk;;;;

Server: Microsoft-IIS/10.0

WWW-Authenticate: Negotiate,NTLM

X-Powered-By: ASP.NET

X-FEServer: MAIL

Date: Sat, 16 Mar 2024 17:50:35 GMT

Content-Length: 0

 

--- RESPONSE BODY [+0.719] ---

--- RESPONSE DONE [+0.720] ---

 

EXCEPTION THROWN [+0.768]

 

HTTP Response Headers:

request-id: c62cb78d-6116-4910-a6c7-f161fabe9104

X-OWA-Version: 15.2.1118.7

X-FailureContext: FrontEnd;401;VW5hdXRob3JpemVk;;;;

Server: Microsoft-IIS/10.0

WWW-Authenticate: Negotiate,NTLM

X-Powered-By: ASP.NET

X-FEServer: MAIL

Date: Sat, 16 Mar 2024 17:50:35 GMT

Content-Length: 0

 

HTTP Status Code: 401 Unauthorized

 

Answer 1

Hi @PM ，

From the description, in case it's an issue related to what is mentioned in this document, please try changing or adding the following registry value and see if there would be any improvement:
(Important: Follow the steps in this section carefully. Serious problems might occur if you modify the registry incorrectly. Before you modify it, back up the registry for restoration in case problems occur.)

Key: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Internet\
Value name: EnableHttpAccessTypeAutomaticProxy
Type: REG_DWORD
Value data: 0

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