“Unable to Upload”, “Couldn’t Sync [number of items] to iCloud”, and notices that particular items could not sync all identify an item-level iCloud Photos failure in Photos on Mac. They do not establish a specific file defect or a library-wide outage. On currently documented macOS releases, the safest first action is to locate the affected items and export them as unmodified originals—without deleting anything until the exports have been checked.
This procedure applies to Photos on Mac with iCloud Photos enabled. Apple does not state that it is limited to macOS Tahoe 26, and Tahoe-specific wording has not been manually verified for this article.
Confirm that this is the “Unable to Upload” item-level error
Use this check before entering the destructive recovery sequence. According to Apple’s Photos library status guide, the affected items are exposed through the library status or the Unable to Upload album.
- Open Photos and select Library.
- Click All Photos, then scroll to the bottom.
- Read the exact library status. If it says that items could not sync, click View, or select Unable to Upload in the sidebar.
If the status instead says Low Data Mode or Low Power Mode, adjust that setting as appropriate. For Optimizing Battery Power, Optimizing System Performance, or Poor Network Connection, wait or use Sync Now if offered. If iCloud storage is full, reduce storage use or upgrade storage. These are temporary or capacity-related states, not the exact item-level error covered by the deletion workflow.
Expected result: You identify whether Photos has isolated particular items in Unable to Upload. This check is low risk and requires no destructive change or rollback. See Apple’s paused iCloud Photos guidance for the documented distinctions.
Protect the affected originals before deleting anything
Use this sequence only when Photos shows the Unable to Upload item-level state. Choose an export destination with enough available space before starting.
- Open Unable to Upload.
- Press Command-A to select the affected items.
- Choose File > Export > Export Unmodified Original For [number] Photos.
- Click Export, choose the save location, and then click Export Originals.
Required safety checkpoint: Do not delete the library items yet. Confirm that the destination contains the expected exported files, compare the exported count with the selected count, and confirm that the exports can be opened or otherwise read. This is an editorial safety checkpoint, not an Apple-prescribed Mac verification method. Checking only a representative sample does not prove that every export is usable.
If files are missing, the count does not match, or any required original cannot be read, stop before deletion. Do not assume that a visible preview means the exported original is recoverable.
Metadata warning: Apple warns that edits and keywords applied in Photos will be lost or might be lost after reimport. The supplied evidence does not establish whether captions, favorites, album membership, dates, Live Photo pairing, or other Photos-specific organization will survive. Preserve any information you cannot afford to lose before continuing.
Do not turn iCloud Photos off and on as a reset. Apple says turning it off restarts syncing and does not recommend it as the first response to this error. The documented item-recovery procedure is in Apple’s Unable to Upload recovery instructions.
Delete and reimport the verified originals
Proceed only after every original you intend to recover has been exported and checked. This stage is high risk because it includes permanent deletion.
- With the affected items still selected in Photos, choose Image > Delete [number] Photos or Videos, then confirm.
- Open Recently Deleted. Delete only the just-deleted items, or choose Delete All if that is appropriate for everything currently there.
- Choose File > Import and select the previously exported images.
- After import, return to Library > All Photos, scroll to the bottom, and check whether the reimported items resume iCloud Photos synchronization.
Rollback boundary: Before Recently Deleted is emptied, the deleted library items remain recoverable there. After permanent deletion, recovery depends on the verified exported originals or another backup.
Expected result: Photos imports new library copies from the exported originals and may resume syncing them to iCloud. This is not guaranteed, and the previous Photos edits and keywords should not be expected to return.
Stop if an original cannot be exported, opened, copied, or reimported
Do not permanently delete an affected library item if its export cannot be verified. Stop the procedure and use Apple Support when an original cannot be exported, opened, copied, or reimported. The error alone does not confirm a particular format, codec, or corruption problem.
- If exporting or copying produces Finder error code -36, use that separate file read-or-write error guide rather than diagnosing it as part of the iCloud sync failure.
- If the Photos library or export destination is on storage that independently reports filesystem errors, and Disk Utility reports that First Aid failed, use the separate storage-repair guide.
Do not rebuild or replace the Photos library, create a new library, run disk repair, erase storage, or disable iCloud Photos as an unverified substitute for recovering the affected originals.