mark of the web

Mark of the Web (MOTW) is a Windows security attribute that flags files downloaded from the internet or other untrusted sources, prompting applications like Microsoft Office to open them in Protected View or block macros. Recent Windows updates, including the June 2026 security patches, have extended MOTW-like trust checks to desktop.ini files, causing custom folder icons and localized names to disappear when Windows cannot verify the file's origin. OneDrive 26.002 now adds MOTW to Outlook attachments saved to synced folders, affecting VBA workflows. Users and IT administrators can manage MOTW through Trust Center settings, Group Policy, or by unblocking files, but should weigh security implications before disabling the protection.