If you currently own a licence for NetProxy 3 you may upgrade to version 4 at a much reduced rate. To obtain your upgrade please visit:-

Upgrade to NetProxy 4 from version 3

If you are a registered user of NetProxy 4 and wish to purchase a licence to cover additional users, you may obtain a licence upgrade. Pricing information for upgrading can be found here. To obtain your upgrade please go to:-

Upgrade NetProxy 4 to cover more users