There are 3 ways Backup Exec 2012 can be licensed:
A. import a Symantec License File (SLF)
1. From the “Add Licenses” screen, click Import From File.
2. Browse to the location where to you saved the .slf file.
3. Select the SLF.
4. Click Open.
B. type the serial numbers (NOTE: This requires an Internet connection and the availability of port 443)
1. From the “Add Licenses” screen, enter the serial numbers that are listed on your license certificate.
2. Click Add.
3. Click Next to submit the serial numbers for verification.
C. install a 60-day trial version
Even after everything seems to be entered properly this problem can occur under the following circumstances:
Maintenance serial numbers were entered and not the Product serial numbers
During the installation in “Activate licenses for Backup Exec, agents, options, or maintenance contracts” look under the "Product Name/Description" to verify which serial numbers were installed. Maintenance and Product serial numbers are identified here
Product serial number checkboxes werent selected in "Select the products to install on this computer
In the "Select the product to install on this computer" screen it shows the “Product” serial number and a checkbox. If nothing was checked, then Backup Exec 2012 will be installed as a Trial version
If Service Pack 1a has not been installed
When adding a new feature/agent licensing after the product was already licensed, prior licensed items may become deselected and put into trial mode. This issue was resolved by Backup Exec 2012 revision 1798 Service Pack 1a. See http://www.symantec.com/business/support/index?page=content&id=TECH189907