User ID is an optional identification that allows software developers
to identify each individual Key of the distributed applications. That is, User
ID allows you to identify each individual user of the protected application.
User ID is needed when using the Remote Key Update Broadcast (RKUB) feature.
When each user is assigned a User ID, you can simply broadcast a single update
file that specifies Key Properties for each user. User ID is also used in the
Activation Server solution. When adding a new activation account, a User ID is
randomly generated and is recorded in the database. This allows Activation
Manager to remotely manage licensing the protected application. If you use the
KeyCheck API, User ID may be used for other purposes as you wish. User ID is 32
bits long, with its value ranging from one to 231.