Why your iPhone photos will not open on Windows

A file called IMG_4471.HEIC arrives from somebody's iPhone and Windows Photos answers with a grey rectangle or a complaint about an unsupported format. The photo is intact. Windows simply does not decode it, and Microsoft's remedy arrives in two parts rather than one.

What a HEIC actually is

Apple switched the iPhone camera to this format with iOS 11 in 2017 and has not looked back. The gain is real: Apple's HEIF and HEVC guide puts it at about half the storage of a JPEG for the same visual quality, which across a few thousand photos is the difference between a phone that fills up and one that does not.

The name covers two things stacked together. HEIF is the container, the box that holds the file. The picture inside it is compressed with HEVC, the same codec used for 4K video. Windows treats those as two separate problems, which is the whole source of the trouble.

The format also carries things a JPEG cannot. The depth map behind Portrait mode, the extra frames that make a Live Photo move, and edits stored alongside the original rather than burned into it, so cropping and filtering stay undoable. None of that survives a conversion, and most of the time none of it matters.

Windows needs two add-ons, not one

The first piece is HEIF Image Extensions, free from the Microsoft Store. Install it and Windows understands the container. Thumbnails start appearing in File Explorer, which makes it look as though the problem is solved.

It is not, because the picture data inside is HEVC and that needs its own decoder. The Store listing most people land on is HEVC Video Extensions at $0.99. Charging a dollar to open a photograph strikes most people as absurd, and the reason is licensing rather than greed: HEVC carries patent fees that Microsoft pays per install.

The better fix is on the phone

Everything above treats the symptom. The cause is that the phone is producing a format the recipient cannot read, and the phone has two settings that deal with it.

The blunt one is the camera format. Apple's camera settings guide covers it: Settings, then Camera, then Formats, then Most Compatible. From that point the camera writes JPEG and everything opens everywhere. The cost is roughly double the file size and no depth data, which matters if you use Portrait mode and does not if you do not.

The better one is almost unknown. In Settings, then Photos, at the bottom under Transfer to Mac or PC, choose Automatic instead of Keep Originals. The phone carries on storing HEIC and saving space, and converts to JPEG on the way out over the cable. You get the storage saving and the compatibility, which is the arrangement most people wanted in the first place.

When the photos are already on the machine

None of the phone settings help with photos somebody already sent you. Converting does, it costs nothing, and it installs nothing.

Where they are going decides the format. JPEG if they are staying photographs and heading into an album, a slide or an email. PDF if they are going into a document, a claim or an application, particularly anything with an upload box that says to attach as PDF.

That second case turns up far more than people expect: proof of damage for an insurer, receipts for an expense claim, a passport and a utility bill for an application, condition photos at the end of a tenancy. Several images, one file, in the order you chose, which is a much easier thing for the person at the other end to handle than nine separate attachments.

What a conversion costs

HEIC and JPEG are both lossy, so converting re-encodes the picture rather than repackaging it. A single pass is invisible at any sensible quality setting. Repeated round trips are not, so convert from the original each time rather than from the last conversion.

A Live Photo hands over its still frame and nothing else, because the motion lives in a separate video track that a single image or a PDF page has nowhere to put. Depth data and undoable edits go the same way: the edits are applied, then they are permanent.

The last thing to look at is the metadata. Photos carry the date, the camera, and usually the exact location. Whether a converter preserves that or strips it matters in both directions, and which you want depends entirely on whether the file is evidence for an insurer or a picture going to a stranger.