HEIC Email Attachment Won't Open? Here's Why & How to Fix It

Last updated: January 2026 · 4 min read

You received an email with a photo attachment from an iPhone user. You click it, and your computer either shows an error or asks "what app do you want to use to open this?" The file is .heic, and Windows has no idea what to do with it.

This is one of the most common frustrations when working between iPhone and Windows. Here's what's happening and your two best options to fix it.

Why Won't My Email App Open HEIC Attachments?

HEIC is Apple's proprietary photo format introduced with iOS 11 in 2017. It's the default format for iPhone photos because it saves storage space — HEIC files are about 30–50% smaller than equivalent JPG files with the same quality.

The problem: Windows doesn't have built-in HEIC support. Most Windows email apps (Outlook, Thunderbird, etc.) can't display HEIC files directly. When you receive a HEIC attachment, the email app doesn't know what to do, so it either blocks the file or asks you to choose an app.

      Quick Fact: This isn't a bug — it's by design. Microsoft's email apps were built before HEIC became common, and they haven't prioritized HEIC support. Apple never pushed hard for Windows support either.
    

Option 1: Install Microsoft's HEIF Image Extensions

The official Microsoft solution is to install the HEIF Image Extensions from the Microsoft Store. This is free and takes 2 minutes:

Open the Microsoft Store
Search for "HEIF Image Extensions"
Click Install
Restart your email app

After installation, HEIC attachments will open directly in Windows Photo Viewer or your default image viewer. This works on Windows 10 and Windows 11.

Pros: Official, free, permanent solution. Once installed, all HEIC files work across Windows.

Cons: Requires installation. Recipients still need to do this on their computers if they want to view HEIC.

Option 2: Convert HEIC to JPG (Recommended for Sharing)

If the email sender just needs you to be able to view the photos, ask them to convert HEIC to JPG before sending. JPG is universal — every device, every email client, every web browser opens JPG natively.

They can use this free tool to convert in 30 seconds without uploading to any server. Conversion happens entirely in their browser, and their photos never leave their device.

Convert HEIC to JPG free — send it back to the sender

Convert now →

What About Your Received Files?

If you've already received HEIC attachments in email, you have three options:

Ask the sender to resend as JPG — fastest if you have ongoing contact.
Use this tool to convert — download the HEIC from your email, convert it here (no upload), and you'll get JPG.
Install Microsoft's HEIF extensions — solves the problem for all future HEIC files on your computer.

Why This Keeps Happening

Apple's iPhone is the world's most popular smartphone. Every person with an iPhone and family members using Windows will eventually experience this problem. It's a compatibility gap that's existed since 2017 and doesn't appear to be closing.

The best long-term approach: educate your iPhone-using contacts that they should convert to JPG before emailing to Windows users, or set their iPhone to save as JPG instead of HEIC (Settings > Camera > Formats > Choose "JPG" instead of "High Efficiency").

Bottom Line

HEIC email attachments don't open on Windows because Windows doesn't have native HEIC support. You can either install Microsoft's free HEIF extensions, or ask senders to convert to JPG (universal compatibility). This tool makes JPG conversion instant, private, and free — your photos never leave your browser.