To resolve this issue you need to download the database manually. Follow the below steps:
1. In the Management Console, select Configuration >Threat Protection > Policy Services > Download.
2. On the Download tab, click Download Now.
Verify the Database Download
To verify that the database was downloaded, check the License and Download Status section on the Download tab.
In addition, the License and Download Status field on the Download tab shows statistics about the previous successful and unsuccessful downloads. If the last download was unsuccessful, the field contains an error.
If you receive a download error, check your network configuration and make sure that the appliance can connect to the Internet or internal server.