Hi Kyle's Mom! This topic is a bit old, so it might be that the problem described in the earlier post is caused by a different issue.
Kindly clarify what you're experiencing so we can find a solution for you:
1. Was your license key suddenly deactivated?
2. Were you installing Little Math on a second (or on a new) PC and your key didn't work in that new installation?
3. Did you get any specific error message?
Please write to us directly at support[at]brillkids[dot]com so we can provide further assistance.