I have reinstalled MoviEZ HD and the software is asking me to enter the serial number. I have entered my serial number exactly as it appears under My account / My products and it is telling my that the serial number is incorrect. I have also tried it with out the dashes and get the same result.
Assuming you mean Sony moviEZ HD - then this is the wrong forum, however the program is obsolete, released in 2012, given the age of the program, is probably trying to contact the Sony registration server which no longer exist, the product, and AFAICS, is also not supported by Magix/Vegas Creative Software.