It means that you have a missed call
go to File->Management Tools->Call History
and you will see
From ooVoo site:
".... all ooVoo users must be 14 years old or older and we check this with your birthday"
I guess you are talking about making a oovoo call. Follow the steps :
1. Download oovoo client on mobile or PC
2. Register an account with oovoo
3. Add friends.
4. Click on friend to call a friend.
5. Video talk as long as you like.
On ooVoo if you receive a message that states they are unable to process your registration you need to try to register at a later time. You may be receiving the message because their servers are unable to process your request at that time. The message may also mean that there is some problem with the information you are trying to enter.