This is my solution, alhamdulillah it worked.
- Open Notepad as Administrator.
- Open this file %windir%\system32\inetsrv\config\applicationhost.config
- Press Ctrl-F to find word "handlers accessPolicy"
- Add word "DELETE" after word "GET,HEAD,POST".
- The sentence will become <add name="PHP_via_FastCGI" path="*.php" verb="GET,HEAD,POST,DELETE"
- The word "PHP_via_FastCGI" can have alternate word such as "PHP_via_FastCGI1" or "PHP_via_FastCGI2".
- Save file.
Reference: https://docs.microsoft.com/en-US/troubleshoot/iis/http-error-405-website