. . . . is there a way to restore an activation code for MEP14 . . . .
Assuming you do mean Movie Edit Pro 14, released 2008.
Is the program is not activated with the P- the serial number, login in to your account at magix.com, using the email address and password you originally registered the software with, under My products .
OR
. . . . need code to burn DVD . . .
Is the program asking you to activate a codec before burning?
If so, this is most likely to be the Dolby AC3 surround sound codec, which is no longer supported/available due to licensing issues with Dolby.
You should be able to burn using the stereo audio preset option.
What is your Windows version? There may be other issues awaiting you, such as actually burning the disc once past the codec issue.