You can NOT add two licences together. For instance if you have a 10 user licence, you cannot buy a 5 user licence and add the two licences to make a 15 user licence. You must buy a 10 to 25 user licence upgrade to give you 25 users.
You can buy upgrades online from our website online order system. You will be issued with a the new licence codes immediately.
Upgrade prices are the difference in price between the two licence sizes, plus a 10 UK pounds administration charge (plus VAT if applicable).
You will not need to reinstall the VPOP3 software or make any configuration changes other than to enter a new licence code and add any new users you want to add (and any settings associated with these new users).