The following works for Windows 8:
First, set XAMPP controller to run at windows startup
- Right click Windows icon, select RUN
- In the Open input box, type in shell:startup, click OK
- Right click on the starup window. Select New->shortcut. Enter path to xampp controller application. In my case it is C:\xampp\xampp-control.exe
- Save everything. This will start the xampp-control panel at startup
Second, configure Apache to start automatically
- Click config button at the upper right hand corner of xampp control panel
- Select autostart modules. It could be a combination of Apache, FileZilla, Tomcat, MySQL, and Mercury
- Save everything
Third, configure firewall to enable XAMPP working over LAN