Apache is not running from XAMPP Control Panel ( Error: Apache shutdown unexpectedly. This may be due to a blocked port)

Question

I have installed XAMPP (xampp-win32-1.8.2-0-VC9-installer.exe) on Windows 7 successfully. But unfortunately, the following error was found during running Apache from XAMPP C

Answer 1

Accompanying Timmay's answer, You need to do two changes-

Listen 80 --> Listen 81 (near line 58)

ServerName localhost:80 --> ServerName localhost:81 (near line 218)