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How do I solve a 401 Unauthorized - IIS Permissions error?

kkluth asked
Medium Priority
Last Modified: 2012-05-06
Currently have a intranet application that uses Windows Integrated Authentication to validate the users.  We don't allow anonymous access to the site.  The server is currently being run on a Windows 2000 server with IIS 5.0.   The drive has NTFS permissions.

One of our pages will read a certain directory for the file information and provide link to an XML file, so the user can click on and view the contents of that XML file.

After the page has successfully read the directory and provided the appropriate link, clicking on the link for the XML file, returns HTTP 401.1 - Unauthorized: Logon Failed.  

This message is found in the System Event Log
Event Type:      Warning
Event Source:      W3SVC
Event Category:      None
Event ID:      100
Date:            2/11/2009
Time:            11:55:47 AM
User:            N/A
Computer:      <server_name>
The server was unable to logon the Windows NT account 'IUSR_<server_name>' due to the following error: Logon failure: the user has not been granted the requested logon type at this computer.  The data is the error code.

I have looked at several articles pointing me in the direction of making sure that IUSR_ has "Logon Locally" and "Access computer from Network".   This user has those permissions.

I have verified that the NTAuthenticationProviders is NTLM, Negotiate.

What am I missing or what should I look at to solve this problem.  Do I need to set "Read" File permissions on that folder and the files within that directory for the IUSR_<servername>?

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Infra Team Lead
Top Expert 2008
1. Ananynmous is disabled as only authenticated users are allowed to access.

2. Does the user or the group which has access over this share given permission....

Rt click the site folder in server and see in permissions if the group or the user who have access to this location are given proper permission....

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Thank you for your response as it helped point me in the right direction.  Within IIS the folder turned on Integrated Security.  Works fine.
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