It is now possible to replace the Trend Micro PC CILLIN serial number with a new one by making changes in the Windows registry. Use REGEDIT to modify the Trend Micro serial number registry entry with the Trend Micro PC CILLIN new serial number. We recommend that you back up the registry before making the modifications,so that older settings can be restored if there is a problem. No hardware modifications are required to change the Trend Micro serial number to a Trend Micro PC CILLIN new serial number. The process to replace the Trend Micro PC CILLIN serial number is complete after the new serial number is registered with the Trend Micro.
Here is how to replace your old serial number with the new one.
Go to registry:
Go to "Start > Run"
Type REGEDIT and click "OK"
In the open window under "My computer", go to "HKEY_LOCAL_MACHINE > SOFTWARE > Trend Micro > PC Cillin"
On the right side of the window, right click on the file "Register no" and select "Modify"
Clear everything and click "OK"
Close all windows
Open PC Cillin
In the left tab, click "Update Registration" and select "Registration" in the right one