防毒軟件的問題

This is depends on what software licensed you have purchase.
For kaspersky internet security....
it have some licensed is for 1 machine ( per machine )
some licensed is 1 licensed (one key) for 3 machine .....
suggest you can check with Kaspersky with your serial key as below

http://support.kaspersky.com/support/international

kaspersky internet security就唔知，但有部份原裝碟，例如norton internet security係有可裝2部or以上的電腦的光碟，但1個licence就一定唔得！