Somebody passing off Home Basic or Business, or even an "N" version, as Home
Premium maybe?
(N versions don't include Media Player)
If you open a command prompt then enter in "slmgr -dli" without the quotes
Vista will report the version, your license status and also give a partial
product key (last 5 digits) that should correspond with either the key you
entered in during installation or with the automatically assigned numbers
for the Vista versions below.
The default partial product key values if you don't enter a key when
installing Vista are:
Business - MRW4W
BusinessN - QXX44
Home Basic - 3V4VD
Home BasicN - GFJBT
Home Premium - 76PKF
Ultimate - RP8F7
In any case if the Vista discs are OEM it's up to the OEM supplier to remedy
your situation.