Security News > 2021 > October > Windows 11 incompatible with apps using non-ASCII registry keys
Microsoft is blocking Windows 11 upgrades if customers use applications that create registry keys using some non-ASCII characters.
"Compatibility issues have been found between apps using some non-ASCII characters in their registry keys or subkeys and Windows 11," Microsoft explains.
Even thought it doesn't say it on the known issue's Windows Health dashboard entry, Microsoft has merged it with a previous bug preventing Cốc Cốc browser users to upgrade to Windows 11.
Microsoft has applied a compatibility hold to safeguard the users' experience by blocking affected Windows devices from being offered or installing Windows 11.
Windows 11 was released worldwide last week and is now rolling it out via Windows Update to new Windows 10 devices and to those pre-loaded with Windows 11.
All Windows 10 users can upgrade to Windows 11 using Windows Update if their systems come with compatible hardware.