launcher check key

[doidloko]

hi i want learn how make a launcher check the key
and u cant use all keys


exemples
47241-7c3c4-6f49c-9b17c-e0740
47241-7c3c4-6f49c-9b17c-e0f01
47241-7c3c4-6f49c-9b17c-e0f02
47241-7c3c4-6f49c-9b17c-e0f03


launcher acept all keys o.o


and how is a query ? query is hard to make ?

for exemple create account and check serial

[MentaL]

[DNC]

Using my build that isn't possible without stopping to get updates.