Legitimate Microsoft .NET Framework installers typically use names like dotnetfx.exe, dotnetfx35.exe, or ndp48-x86-x64-allos-enu.exe. There is no official Microsoft product named ".NET 365." The "365" suffix is likely a tactic used by attackers to make malware look like a modern Microsoft 365 (formerly Office 365) component. Official .NET Framework facts
.NET Framework: A software framework for building and running Windows applications. dotnetfx 365.exe
Because "dotnetfx" installers require administrative privileges, they are often used by bad actors to disguise malware. Microsoft .NET Framework 3.5 Service pack 1 (Full Package) Legitimate Microsoft
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