Microsoft has issued a warning for Windows 7 users that want to download the Multilingual User Interface (MUI) packs. According to the company, the MUIs are only meant for Windows 7 Ultimate and Windows 7 Enterprise editions. Those who download and install the packs on any other version of Windows 7 will receive a non-genuine warning when trying to install updates or files from the Microsoft Download Center, even though the OS is actually legit.
"Multilingual User Interface (MUI) packs require a license to be used and are available only for Windows 7 Ultimate and Windows 7 Enterprise editions," Microsoft said. "If these language files are present on another edition of Windows 7, genuine technologies will detect tampering on the system and display the non-genuine warnings."
In essence, your OS is now deemed as pirated despite your expensive license keys. Typically the warning will say: "this copy of Windows is not Genuine." To fix the problem, Microsoft said that customers must either remove the MUI packs, or format the HDD and re-install Windows 7. While the former option sound less troublesome, users will need to uninstall the packs using the same 3rd-party program initially used to install the MUIs in the first place.
Ultimately, consumers using Windows 7 Home Basic, Windows 7 Home Premium, and Windows 7 Professional should steer clear of the MUI packs.