My Passport Pro replace disk No WiFi key connect

after replace the disk on a My passport Pro , i can see the WiFi network but i cant connect to it
with the current key

i found it
when replace the disk on mypassport wifi device the key for the wifi is , the 8 characters after the first four characters of the serila number of the new disk NOT THE LAST 8 characters , because the new disk can have longer serial number