32 bit Windows
"C:\Program Files\Skype\Phone\Skype.exe" /secondary
64 bit Windows"C:\Program Files (x86)\Skype\Phone\Skype.exe" /secondary
If you always need 2 or more Skype Account to be opened
Right click --> Create shortcut -->
Give it a Name , and a shortcut to open Multiple Skype is done
Hope it helps