I got a pc off of ebay and i have an old dell e510 with windows xp home edition ive tryed to use the key on the tower but it just says that i cannot use it
No - you can't.
OEM Keys such as those from Dell are locked to the OEM PC with which they were provided, and are not valid on any other machine/
You need to purchase a new Full License for windows from a reputable store.
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Noel Paton | Nil Carborundum Illegitemi |
CrashFixPC |
The Three-toed Sloth