ASEBA-PC is a single user license; you can only install it on one computer. If you'd like to use it on more than one machine, you have a few options:
1. Purchase multiple licenses for ASEBA-PC.
2. Purchase a yearly subscription to ASEBA-Web. ASEBA-Web works on a system of e-units. Each form you send out costs 2 e-units, and you can see the price of additional e-units here: http://store.aseba.org/ASEBA-Web-Products/products/24/. The primary advantage of ASEBA-Web, besides being able to use it on any computer, is that it provides informants access to a site where they can fill out the forms themselves. This may save you time since you won't have to key-enter the forms one by one.
3. Purchase ASEBA-Network. ASEBA-Network runs on a server on your network. You can then access it from any computer with a web browser. You can see the installation requirements here: http://aseba-network.aseba.org.