Port 443 in use by "Unable to open process" with PID 4

Similarly, I experienced this: Port 443 in use by "Unable to open process" with PID 6012! When starting XAMPP Control Panel v3.2.1 for the first time.

In Task Manager I found that PID 6012 was Apache web server. A copy of it was running in the background without the GUI, and when I invoked the GUI it was trying to start another copy. Killed the phantom copy and then XAMPP started up fine.

I didn't have to change any port settings.

I had the same problem: port-443-in-use-by-unable-to-open-process-with-pid-4

First I disabled the weather tile in Win* that apparently phones home to Redmond for updates after this showed on netstat list.

This didn't solve the problem. I looked at the post already here which mentioned VPNs, so I went to Control Panel\Network and Internet\Network and Sharing Center and clicked on Change adapter settings

I clicked on Incoming Connections and right clicked on properties

The VPN click box at the bottom of the General tab was on, so I unchecked it

Under Users, I also unchecked a previous user I had allowed to copy some data weeks before

Then I clicked okay

Closed the control panel and restarted the XAMPP control panel

It fired right up without a problem.

Just change the sll port in httpd-ssl.conf file. It would be under C:\xampp\apache\conf\extra. Find "443" and replace it with other values(e.g 8181), then start your apache again