Why did IIS ApplicationHost.config file disappear?

Question

Hello,

Currently, I am operating two cloud-based instances of Windows Server 2012 and 2016.

In IIS, when I try to add a binding or modify the application pool, the changes are not saved, and I encounter the following error:

C:/Windows/system32/inetsrv/config/applicationHost.config

Error: Cannot write to the configuration file.

When I navigate to the specified path, the applicationHost.config file does not exist.

In the case of Windows Server 2012, it seems that the file was removed after an update.

Additionally, for the Windows Server 2016 instance, there are no backup files available in C:\inetpub\history.

Would anyone be able to provide insights into the possible cause of this issue or suggest a solution?

Thank you in advance for your help.