When you update your iPhone to iOS 11, you may find that your photos become HEIC format and they cannot be read on Windows. There are 4 solutions in the article
This article examines 2 ways to convert iPhone HEIC photos to JPG. The methods are applicable to iPhone X/8(Plus)/7(Plus)/6s(Plus)/6(Plus) with iOS 11.
Are you thinking of using Heictojpg.com to convert your HEIC/HEIF photos? You should read this before you try it.
Are you thinking of using Apowersoft’s HEIC converter? Learn about this web app and some of its alternatives here.
Easily convert Apple's latest iOS 11 images from HEIC to JPG
Convert HEIC Photos to JPG
Flexible HEIC Converter
Complete iPhone Media Solution