Step 1

Bvckup is designed to try and retrieve its evaluation license automatically. In environments where the Internet connectivity is restricted or unavailable, the automatic retrieval may fail with the following message:

Step 2

Select the Installation ID indicated by the red arrow and copy-paste it here:

Step 3

Once you click on Retrieve License button below, the server will send you a file called "bvckup.lic". This file contains your evaluation license and it needs to be saved in the Bvckup configuration folder.

The location of this folder on Windows XP is:

%UserProfile%\Local Settings\Application Data\Bvckup

On Windows Vista and Windows 7 it is:

This is the original version of Bvckup. It was written for Windows XP, last updated in 2010 and it's now well behind times. Use at your own risk, basically.
It has been superseded by Bvckup 2 - a faster and significantly more refined revision of the same idea. Have a look.