Look for a string value ( REG_SZ ) named SerialNumber .
: If Nitro Pro 10 is currently installed and activated, you can often find the key in the registry at: HKEY_LOCAL_MACHINE\SOFTWARE\Nitro\Pro\10\Registration (or similar path under Nitro Support Tools : Open Nitro Pro, go to the tab, and select Support Tools Nitro Pro 10 Serial Number Key Finder