iPhone 8 Plus/iMac Photos not uploading to iCloud

Some pictures transferred by cable from a computer to an iPhone are treated as temporary, and the expectation is that the originals are still on the computer. So these "From My Mac" pictures can't be edited, printed, or deleted on the phone, and they can't be synchronized with iCloud Photos. If you don't still have these in your Mac Photos Library, then Matti Haveri's suggestion is exactly right-- to keep them you need to get them under the control of the Photos app. This applies to as well to other pictures that aren't completely controlled by Photos.

As Matti suggests, since you have a Mac, you may be able to use the app Image Capture from your Applications folder to transfer the pictures to your Mac and to Photos. This seems like the best bet. Be careful to make sure you get all the ones you want to save-- sometimes Image Capture may miss some.

Or you can use the iPhone to save them to Files and then re-import them to Photos. You can use Files>iCloud Drive or or Files>External Drive. If you use Files>On My iPhone, then you'll want to delete them after you're sure they are safely in Photos on your Mac or iPhone.

If you do still have these pictures on your Mac, and if they won't upload to iCloud, then you should try to export them and then re-import them to Photos on the Mac. If you have them on the Mac and they won't export, then we might be able to help--maybe.

Let us know how it goes…

Rivergull wrote:

"could not sync 229 items to iCloud." When I tap "View" it lets me see thumbnails of those 229 items. Some have visible images, some are blank.

80% or more are .jpg's (shot with my own camera, OR screenshots, OR scans I made of documents or vintage paper snapshots using my own printer/scanner). The rest are marked either .bmp, .tiff, .png, or .AVI.

If you have basic Terminal skills you could try to identify images which don't sync to iCloud and then try to find out what they might have in common. Maybe they use some old now-incompatible codec and therefore fail to sync.

For example, .avi movies are not supported at least now (if ever) and I wonder how such movies have slipped into your Photos library. A few years ago while still running Mojave I filtered such movies shot with old cell phones and converted them to currently supported video and audio codecs and wrappers.

Can you export images that fail to sync to the local Finder folder? If yes, you could then carefully delete them from the Photos library and try to find out if there is something wrong with them (wrong extension, metadata corruption etc) that could be fixed.

Rivergull wrote:

Why do I need to import images from my iPhone over to my iMac if my iPhone and iMac are already synced to each other. I can go to Photos on my iPhone OR Photos on my iMac and see the very same collection of images/photos, including the 'unable to upload' (unviewable) images.

Oh sorry, I did not fully understand the situation and thought the images were stranded only in the old iPhone 8.

So the problem is that about 300 images can't be uploaded to iCloud Photos (from the old iPhone 8 and from the iMac) and you don't exactly know which ones, right? And you want to get the situation corrected before bringing a new iPhone to the mix, right?

Well, that is a messy problem. I guess the best way to start is to make a backup of the iPhone (to the iCloud and/or locally to the Mac) and the Mac (with Time Machine or Carbon Copy Cloner to an external disk). And maybe also export images (either originals or edited, it's your call) to a Finder folders from the iPhone Photos and from the iMac Photos (...this might be overdoing backups but it is better to be safe than sorry).

After that you are more free to experiment and do mistakes, and start over, if necessary.

If all else fails, I'd create a new Photos library from scratch and import to it from the backup(s). And check if those backups might differ and have different amounts of images.

I let others chime in how they'd fix this with minimum fuss.

The iMac M1 Photos library is using iCloud Photos, right? If yes:

Use Application/Image Capture.app to import images from the old iPhone 8 via USB cable to the iMac's Finder folder. Then import them to Mac's Photos library and let the images upload to iCloud Photos.

p.s. What kind of images fail to upload? Plain vanilla .jpg or .heic images (or movies?) shot with the iPhone or some images with maybe incompatible codecs?

Rivergull wrote:

Is the ImageCapture.app something I can find in the Apple Store?

It is at Applications/Image Capture.app. I have always used it to import images from iPhones, cameras, memory card readers etc.