Hello kiwilink,
Welcome to Apple Support Communities!
We want to help you transfer the movies from your iPhone to your Windows PC.
Let's make sure you're using these steps to transfer the movies:
"Import to your Windows PC
You can import photos to your PC by connecting your device to your computer and using the Windows Photos app:
- Update to the latest version of iTunes on your PC. Importing photos to your PC requires iTunes 12.5.1 or later.
- Connect your iPhone or iPad to your PC with a USB cable.
- If asked, unlock your iOS or iPadOS device using your passcode.
- If you see a prompt on your iOS or iPadOS device asking you to Trust This Computer, tap Trust or Allow to continue.
Then, visit Microsoft's website to learn how to import photos to the Windows Photos app in Windows 10.
If you have iCloud Photos turned on, you need to download the original, full resolution versions of your photos to your iPhone or iPad before you import to your PC.
When you import videos from your iOS or iPadOS device to your PC, some might be rotated incorrectly in the Windows Photos app. You can add these videos to iTunes to play them in the correct orientation.
If you want to ensure photos from your iOS or iPadOS device have the best compatibility with Windows 10, try these steps:
- On your iOS or iPadOS device, open the Settings app.
- Tap Camera, then tap Formats.
- Tap Most Compatible. From now on, your camera will create photos and videos in JPEG and H.264 formats."
This Apple Support page has the full details: Transfer photos and videos from your iPhone or iPad to your Mac or PC - Apple Support
We hope this helps to get the files transferred over to your PC and resolve the issue.
Cheers!