can some help me to solve the 0x80070021 error

I am new to iis, when I try to access the site, I get the following error：

Module
IIS Web Core

Notification
BeginRequest

Handler
Not yet determined

Error Code
0x80070021

I tried to search for similar problems through Google, and tried the steps in the link below, but without success.

HTTP Error 500.19 and error code : 0x80070021

Can some one help me? Thanks in advance.

According to your description and error mesage, it seems something wrong with your web.config.

The 0x80070021 error occurs if the specified portion of the IIS configuration file is locked at a higher configuration level.

I suggest you could refer to below article to know how to unlock the configuration.

How to Use Locking in IIS 7.0 Configuration