Yuck. Sorry that you had a bad experience. It sounds like you hit a nasty sync bug on the destination machine. We've been patching a bunch of issues with client sync reliability over the last year. It's hard to diagnose at this point, but please reach out if you can reproduce it on the current version.

FWIW, I can say with confidence that your issue had nothing to do with the fact that the file was an Office ISO.

Thanks for your reply. That fills me with a little more confidence. However, elsewhere in this thread someone else raised a valid question:

How do you handle child porn filtering?

I have three children and take photos of them. I am worried about false positivies.

There are 3 processes: PhotoDNA hashing [1], automated flesh tone detection, and manual review.

1. PhotoDNA runs on every upload. It's only used to identify known child pornography that has already been reported, to make sure it can't be re-uploaded.

2. Automated flesh tone detection only runs when a photo is shared. (This is a change in policy; it used to run on upload.) There are heuristics that try to measure whether it's personal sharing or broad sharing, and we're continually improving those. The goal is to make flesh tone detection only run during broad sharing.

3. If the broad sharing criteria is met and automated flesh tone detection triggers a positive result, that is the only case in which an item is anonymously sent to manual review. It's some highly controlled clean-room environment where a dedicated team tries to determine whether the content is a legal risk or not. Clear cases of shared child exploitation porn are reported. (A parent's "baby in bathtub" type of photos are not the target here.) In most cases, it's adult pornography or family photos. In those cases, the folder is marked as porn and simply can't be shared again. (There's a user-visible message on the web UI.) It's not deleted, and it continues to be fully accessible to the owner across all machines.

The scanning policy used to be more aggressive and didn't exclude content that was unshared or only shared to a small set of people. None of us liked that policy to begin with, and then some high-profile false positives helped force the policy to be revised.

[1] https://en.wikipedia.org/wiki/PhotoDNA

I keep reading that OneDrive lets users upload adult porn either through here, or reddit AMAs, etc.

However, the terms that are linked to me at the bottom of OneDrive.com specifically tell me that uploading porn is not allowed and presumably (haven;t double checked) tell me that if I do my MSA will be deactivated.

It's nice to have you and co. tell me that you allow porn, but the fact that the terms I legally agree to contradict what you say sort of puts me in an uncomfortable position.

Have you thought about changing the terms of use to accurately reflect your policies?

Why don't you encrypt those pictures before getting them out of your control on the "cloud"? I would extend this suggestion to every other file but those in particular kind of scary me to be available somewhere else without encryption.

Its a hypothetical question really. I keep everything offline in multiple places.

Might be a dumb question ("have you tried restarting your computer?") but does the ISO come up through the web browser at onedrive.com? You only mentioned checking the sync folders.