I have downloaded an mp4 iMovie to my one drive by cannot view it there as it says the video file is invalid how do I fix this

Hi Daisy Grove,

I haven't received any updates since your message. Has everything been resolved yet?

Hi Daisy Grove,

Thank you for reaching out to Microsoft Q&A Forum. I know how frustrating it is when a video uploads to OneDrive but won’t play, even though it’s in MP4 format. This usually happens when iMovie exports the file using a format that OneDrive’s online player can’t read, even though the file itself is valid.

Here are some more detailed steps you can try to fix the issue:

1. Re‑export the video from iMovie with compatible settings

iMovie sometimes exports MP4 files using codecs that OneDrive can’t preview. Re‑exporting with specific settings usually solves it. In iMovie, go to: File > Share > File, then set:

• Format: Video + Audio
• Resolution: 1080p (or 720p if you prefer)
• Quality: High
• Compress: Faster These settings force iMovie to use a format that works better with OneDrive.

2. Check the file on your Mac before uploading

Open the exported file in QuickTime Player.

• If it plays normally, the file is fine.
• If it doesn’t play, the export may not have completed correctly.

3. Upload the file again to OneDrive

Sometimes the upload can become incomplete. Try:

• Deleting the file from OneDrive
• Uploading the newly exported version
• Waiting for the upload to fully finish before opening it

4. Try downloading the file from OneDrive

Even if OneDrive can’t preview the video online, you should still be able to:

• Click Download
• Play it locally on your Mac This helps confirm the file itself is intact.

5. Check OneDrive’s file size limits

If the video is very large, OneDrive may struggle to generate a preview.

Files over several GB often won’t preview online but they can still be stored and downloaded normally

6. Convert the video to a more compatible format (optional)

If re‑exporting doesn’t help, you can convert the file using a free tool. Choose:

• Format: MP4
• Video Codec: H.264 This creates a version that OneDrive can preview reliably.

Hopefully my response gives you some useful direction toward fixing this. If you try these steps and still can’t view the video, feel free to let me know what happens and I can help you look at the next options.

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