You may find websites offering pre-made "Office 365 ISO" files. as they may contain modified files, malware, or expired trials. Always generate your own offline source using the official Microsoft Office Deployment Tool.
To perform an offline installation of Microsoft 365, you must use the . This tool allows you to download the installation files once and then deploy them to multiple computers without re-downloading.
Standard installations stream files while you install. This is efficient for high-speed fiber but problematic in other scenarios. : Download once, install on ten computers.