The Acer Aspire 4720Z laptop appears to be a very old model which came with Windows XP or Windows Vista 32-bit.
What's the exact Windows version on the Certificate-Of-Authenticity sticker on yours?
What's the exact SNID number and serial number on yours?
What country was it originally purchased in?
That serial number came back "not found" at the Acer support site.
You may have submitted it incorrectly or it may no longer be in Acer's database because of its age.
Anyway, Allan may have found a solution for you.
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