You might be thinking of a very old version of Windows, like 3.1 vintage. 3.1 didn't really have passwords to access the system, it did however have screensave

You might be thinking of a very old version of Windows, like 3.1 vintage. 3.1 didn't really have passwords to access the system, it did however have screensaver passwords which were either plain text or a very weak hash. They could also be disabled by simply deleting the line for a .ini file which was bad considering it didn't have the concept of users who could only access certain files.