You'd trigger Windows Defender's "Controlled Folder Access" only if the user has it on (it's still off by default IIRC due to many, many false positives) and only for write operations. By iterating every file you may trigger its "this might be ransomware" flag but you'll only be stopped when you try to write to a protected folder. (Which is only Documents, Pictures & Videos by default)

But honestly, I've had to whitelist Microsoft's own Windows utilities from CFA in its earlier days, so don't fret about it.

Thank you. I'm deliberately going to be readonly (and most likely only filenames unless the user requests contents) When I'm walking around the filesystem.

Thank you for the info.