XAMPP Apache HTTP server port 80 blocked on Windows 7

For testing websites on my local PC I use XAMPP and with it Apache HTTP server which is configured for the standard ports of 80 and 443. Recently I had a rather persistent case of the webserver just not starting because of something already using port 80. This is on Windows 7 64-bit.

This hunt to get Apache started on port 80 was a long story including a weird error in the log of port 443 being used over port 80.

At one point in time the log files did not get populated either. It helped to start Apache using the XAMP provided batch files to start Apache. This actually showed the error including that logs could not be written.

All of the usual suspects were checked and mostly were either not installed or the suspect services had been previously disabled. This included IIS, SQL Server. web publishing and routing services, etc. The list went on. Eventually I killed most services and processes that could have been remotely related to this and still no luck.

The cause of my problem in the end was this which was still ticked:
Allow Remote Assistance connections to this computer

The next day I checked for the same setting on my PC at work where Apache is running successfully with XAMPP on Windows 8 and found that the checkbox was ticked. The funny thing was that I do not remember that the actual service was actively running. Now I wonder why that remote assistance was actually using port 80 to begin with when Microsoft already has two or three other software pieces that use this port and it is standard HTTP. Going to my localhost address with a webserver (default port 80) was useless. I really wonder why someone implemented this.