HTTP 401.3 Access Denied

Story: Before the day before yesterday, IIS still works normally. after one night, the HTTP 401.3 Access Denied error will be returned when you access the folder again, apparently because the permissions of the Web Folder have been changed, in addition, many friends on the Internet also said this), so they checked the ACL of each folder related to IIS, but found that these folder settings are correct. we are worried that the permission settings for a file are incorrect, but we cannot determine which file is used.

Solution: if you cannot determine which file has incorrect permission settings, you can use a tool provided by Microsoft to help you identify the cause. You can download this tool from the following link:FilemonHttp://www.microsoft.com/technet/sysinternals/utilities/filemon.mspx
The final result of using this tool is that someone has changed the security settings of \ windows \ system32 \ userenv. dll. The user group cannot access this file. After adding the user group, everything is normal.

Notes: Run this tool and set the filter to the directory you want to monitor. We recommend that you monitor the entire c directory and your website folder. analysis: Search for w3wp and Access Denied keywords. When w3wp cannot access a file, check whether the security settings of the file are correct, this method should solve most HTTP 401.3 Access Denied errors :)