XAMPP Installation Error “Port 80 or 443 already in use.Apache2.2 service failed.”

Hello folks,
When I try to launch XAMPP 1.7.1 win 32 in the system I facing some difficulty. The download was good, without any issue. Then I start the installation it went almost to the end like 99% but all of sudden I got this error message. I just followed the instruction to install the software. Don’t understand where I went wrong? Please help. Thanks.

Ports 80 or 443 (SSL) already in use! Installing Apache2.2 service failed
OK
