A Microsoft account or MSA (previously known as Microsoft Passport, .NET Passport, and Windows Live ID) is a single sign-on Microsoft user account for Microsoft customers to log in to Microsoft services (like Outlook.com), devices running on one of Microsoft's current operating systems (e.g. Microsoft Windows computers and tablets, Xbox consoles), and Microsoft application software (including Visual Studio).
Microsoft Passport, the predecessor to Windows Live ID, was originally positioned as a single sign-on service for all web commerce. Microsoft Passport received much criticism. A prominent critic was Kim Cameron, the author of The Laws of Identity, who questioned Microsoft Passport in its violations of those laws. He then joined Microsoft in 1999 after his company was acquired and was its Chief Architect of Access and Identity until his 2019 retirement, helping to address those violations in the design of the Microsoft Account identity meta-system. As a consequence, Microsoft Accounts are not positioned as the single sign-on service for all web commerce, but as one choice of many among identity systems.
In December 1999, Microsoft neglected to pay their annual $35 "passport.com" domain registration fee to Network Solutions. The oversight made Hotmail, which used the site for authentication, unavailable on December 24. A Linux consultant, Michael Chaney, paid it the next day (Christmas), hoping it would solve this issue with the downed site. The payment resulted in the site being available the next morning. In Autumn 2003, a similar good Samaritan helped Microsoft when they missed payment on the "hotmail.co.uk" address, although no downtime resulted.
In 2001, the Electronic Frontier Foundation's staff attorney Deborah Pierce criticized Microsoft Passport as a potential threat to privacy after it was revealed that Microsoft would have full access to and usage of customer information. The privacy terms were quickly updated by Microsoft to allay customers' fears.