If you have a boxed copy of Windows XP, a VLK key will be rejected as "invalid". Retail versions require activation within 30 days via phone or internet.
: Historically, such keys were used by organizations to bypass individual product activation windows xp product key k2kb2 work
Remember, Microsoft no longer supports Windows XP. This means there are no security updates, technical support, or compatibility updates available. If you have a boxed copy of Windows