If you get the error message "The serial number is invalid" when you type your serial number, please check the following things.
The format of serial number is six numeric characters, -(hyphen), and sixteen alphanumeric characters. Count the number of characters to confirm no character is missing.
Confirm each character. Especially following pairs of characters are easy to be mistaken.
O (Opinion's O) and 0 (numeric zero) I (Iron's I) and 1 (numeric one) B (Bee's B) and 8 (numeric eight) Z (Zone's Z) and 2 (numeric two) V (Victory's V) and U (Unit's U)
If your OS lets you use wide characters, such characters might be input as a serial number. Such situation usually happens when you are using non-western language. Because EDIUS doesn’t accept wide characters as serial number, confirm that such character is not used.
If you use a front-end input processor like Japanese IME, input characters might not have been committed. Disable any front-end input processor before input your serial number.