System net webexception удаленный сервер возвратил ошибку 401 несанкционированный

User-650628323 posted

Hi,

I agree with BrockAllen’s opinion. According to your description, you need to add the add Credentials for HttpWebRequest.  

// Assign the credentials of the logged in user or the user being impersonated.
request.Credentials = CredentialCache.DefaultCredentials;

Or

request.Credentials = new NetworkCredential("UserName", "PassWord"); 

For details about it, please
NetworkCredential Class and
CredentialCache.DefaultCredentials Property.

Best wishes,

• Marked as answer by

  Thursday, October 7, 2021 12:00 AM

По поводу предупреждения EventId 6037 от источника LSA (LsaSrv): у вас отсутствует SPN HOST/mail.замазано.su, нужный для аутентификации по Kerberos при обращении к Exchange. Данная ошибка зафиксирована службой мониторинга (судя по имени
exe), но она же может препятствовать доступу как раз клиентов из домена.

Как я понимаю, у вас либо сервер называется не mail, либо домен AD у вас — не mail.что-то-там.su.  Если ни то, ни другое неверно, то, значит, кто-то кривыми руками SPN поправил.

В любом случае, проверьте отсутсвие имени:

setspn -Q HOST/mail.замазано.su

Если его нет — добавьте:

setpn -S HOST/mail.замазано.su NetBIOS-имя-сервера

Слава России!

• Изменено

  14 апреля 2020 г. 15:31

• Помечено в качестве ответа
  Vasilev VasilMicrosoft contingent staff
  27 апреля 2020 г. 8:42

User-2057865890 posted

Hi Jim,

You could create a registry key on the machine that is trying to access the server, and white list the domain you are trying to hit.

• Click Start, click Run, type regedit, and then click OK.
• In Registry Editor, locate and then click the following registry key: HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlLsaMSV1_0
• Right-click MSV1_0, point to New, and then click Multi-String Value.
• Type BackConnectionHostNames, and then press ENTER.
• Right-click BackConnectionHostNames, and then click Modify.
• In the Value data box, type the host name or the host names for the sites that are on the local computer, and then click OK.
• Quit Registry Editor, and then restart the IISAdmin service.

reference: https://support.microsoft.com/en-us/kb/896861 

Best Regards,

Chris

• Marked as answer by

  Thursday, October 7, 2021 12:00 AM

User1760698851 posted

Hi Chris,

Thanks for all your effort  you made . Finally, it is working :

It was not straight forward :

On  the Server , I wasn’t able to access the WEB API & ASP.NET WEB application which was using WEB API to populate the data locally . ( Was helpfull to test locally on server)

step 1 :

You could create a registry key on the machine that is trying to access the server, and white list the domain you are trying to hit.

• Click Start, click Run, type regedit, and then click OK.
• In Registry Editor, locate and then click the following registry key: HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlLsaMSV1_0
• Right-click MSV1_0, point to New, and then click Multi-String Value.
• Type BackConnectionHostNames, and then press ENTER.
• Right-click BackConnectionHostNames, and then click Modify.
• In the Value data box, type the host name or the host names for the sites that are on the local computer, and then click OK.
• Quit Registry Editor, and then restart the IISAdmin service.

reference: https://support.microsoft.com/en-us/kb/896861 

Step 2: Install windows Authentication on IIS  &  Windows Authentication ( under IIS -> Authentication )  on both WEB API & ASP.NET web application

Step 3: 

My final code was ( if you are accessing WEB API & web application from same machine using windows authentication ) from a web application .

private static  WebClient wc = new WebClient();


public static List<Course> GetCourses()

{

    List<Course> courseList = new List<Course>();
     wc.UseDefaultCredentials = true;
    string courses = webClient.DownloadString("http://xx.yy.zz/api/Courses");
    dynamic dynObj = JsonConvert.DeserializeObject(courses);
        foreach (var data in dynObj)
           {
               Course course = new Course((string)data.CourseId, (string)data.CourseCode, (string)data.Description, (string)data.Name, (string)data.TypeCode);
               courseList.Add(course);
           }
     return Course.SortCoursesAlpha(courseList);

}

• Marked as answer by
  Anonymous
  Thursday, October 7, 2021 12:00 AM

User-2057865890 posted

Hi Jim,

You could create a registry key on the machine that is trying to access the server, and white list the domain you are trying to hit.

• Click Start, click Run, type regedit, and then click OK.
• In Registry Editor, locate and then click the following registry key: HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlLsaMSV1_0
• Right-click MSV1_0, point to New, and then click Multi-String Value.
• Type BackConnectionHostNames, and then press ENTER.
• Right-click BackConnectionHostNames, and then click Modify.
• In the Value data box, type the host name or the host names for the sites that are on the local computer, and then click OK.
• Quit Registry Editor, and then restart the IISAdmin service.

reference: https://support.microsoft.com/en-us/kb/896861 

Best Regards,

Chris

• Marked as answer by

  Thursday, October 7, 2021 12:00 AM

User1760698851 posted

Hi Chris,

Thanks for all your effort  you made . Finally, it is working :

It was not straight forward :

On  the Server , I wasn’t able to access the WEB API & ASP.NET WEB application which was using WEB API to populate the data locally . ( Was helpfull to test locally on server)

step 1 :

You could create a registry key on the machine that is trying to access the server, and white list the domain you are trying to hit.

• Click Start, click Run, type regedit, and then click OK.
• In Registry Editor, locate and then click the following registry key: HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlLsaMSV1_0
• Right-click MSV1_0, point to New, and then click Multi-String Value.
• Type BackConnectionHostNames, and then press ENTER.
• Right-click BackConnectionHostNames, and then click Modify.
• In the Value data box, type the host name or the host names for the sites that are on the local computer, and then click OK.
• Quit Registry Editor, and then restart the IISAdmin service.

reference: https://support.microsoft.com/en-us/kb/896861 

Step 2: Install windows Authentication on IIS  &  Windows Authentication ( under IIS -> Authentication )  on both WEB API & ASP.NET web application

Step 3: 

My final code was ( if you are accessing WEB API & web application from same machine using windows authentication ) from a web application .

private static  WebClient wc = new WebClient();


public static List<Course> GetCourses()

{

    List<Course> courseList = new List<Course>();
     wc.UseDefaultCredentials = true;
    string courses = webClient.DownloadString("http://xx.yy.zz/api/Courses");
    dynamic dynObj = JsonConvert.DeserializeObject(courses);
        foreach (var data in dynObj)
           {
               Course course = new Course((string)data.CourseId, (string)data.CourseCode, (string)data.Description, (string)data.Name, (string)data.TypeCode);
               courseList.Add(course);
           }
     return Course.SortCoursesAlpha(courseList);

}

• Marked as answer by
  Anonymous
  Thursday, October 7, 2021 12:00 AM