Huge thanks to 'AItrea' and 'JonB'!
I did as you recommended, that is turning off the 'Microsoft IIS' from the Windows Service Manager thus:
Now, Apache can start and run smoothly...
I'm very happy about this. Thanks to you guys for the wonderful work you're doing here.
Although, I don't know what started and is using the IIS that I stopped, all I know is that my XAMP is running ok!