If you have a license for Studio 14, you can upgrade to a modern version (Studio 25 or Ultimate) at a discount. You do not need the old serial to install the new software; you just need it to prove eligibility for an upgrade.
If you purchased the software as a digital download, search your email archives for the purchase confirmation. Keywords like "Pinnacle," "Cleverbridge," "Digital River," or "Incrediblemail" might help you locate the receipt containing the serial number.
The financial cost of cleaning an infected PC (or losing your data) is far higher than the price of a legitimate license.
Locating the specific for your old key
If the software is still installed on an old machine, the key may be accessible via the "About" or "Help" menu within the application. Activation & Troubleshooting
Ensure all letters are entered in capitals as they appear on the label.