Editing Product key (section)

=== Windows 95 retail key ===
Windows 95 retail product keys take the form XXX-XXXXXXX.<ref>{{Cite web |last=Upadhyay |first=Saket |date=May 14, 2021 |title=Reversing Microsoft's Windows95 Product Key Check Mechanism |url=https://infosecwriteups.com/reversing-microsofts-windows95-product-key-check-mechanism-ca7e825014b6 }}</ref> To determine whether the key is valid, Windows 95 performs the following checks:

* The first 3 characters must not be equal to 333, 444, 555, 666, 777, 888 or 999.
* The last 7 characters must all be numbers from 0-8.
* The sum of the last 7 numbers must be divisible by 7 with no remainder.
* The fourth character is unchecked.

If all checks pass, the product key is valid. Consequently a product key of 000-0000000 would be considered valid under these conditions.