If you are an archivist, consider storing this ISO on a LTO tape or a cold-storage hard drive. For developers maintaining legacy software for the francophone market, having this ISO readily available reduces debugging time dramatically.
If "macossierra10126frenchiso" relates to something else, could you provide more context? macossierra10126frenchiso
As a legacy OS, 10.12.6 no longer receives security updates from Apple. Use caution when browsing the web. If you are an archivist, consider storing this
It addressed critical vulnerabilities that existed in earlier 10.12 versions. If you are an archivist
: Reinstalling the operating system on machines from approximately 2009–2017 that are compatible with Sierra.
Before you start, make sure your Mac is compatible with macOS Sierra. Apple provides a list of compatible devices on its support website.