My sister's laptop had a major meltdown aind when it woke up it didn't want to open Movie Studio. We redownloaded it but now it's coming up with error message 14 and saying that the serial number is invalid or belongs to a different account. It's Movie Studio Platinum 14.0
A possibility is that the email address being used to re-activate VMSP14 is different to the email address originally used to register/activate VMSP14 many years ago. To re-activate Vegas software, the email address used during the activation process must be the same as the one registered on your sister's MAGIX My Account.