My upload stalls, fails, or won't finish

What's happening

The progress bar stops moving, or you get an error partway through the transfer. Either path runs to many gigabytes — a few thousand photos as readily as a finished export — and the upload has to survive the whole way, so a brief network interruption is the usual culprit.

What to check

1. Raw photos — check which step is stuck. Your browser packs the photos into one file before anything is sent, and that reads Preparing … photos; only Uploading… is the transfer. On a few thousand photos, packing is slow without being stalled.
2. Processed export — confirm the file really is a .zip, not a folder or a .rar/.7z, and check whether the deliverables panel scanned it. If it read the contents, the archive itself is fine and readable.
3. Either way — check your connection, particularly whether you are on wi-fi for a multi-gigabyte transfer, and that the machine isn't set to sleep while unattended.

How to fix it

1. Start the upload again. A failed upload creates no project and costs nothing, so there is nothing to clean up first and no credits are consumed.
2. Use a wired connection for anything over a couple of gigabytes — a large photo set as much as an export.
3. Keep the tab open while the transfer runs.

Avoiding it next time

Wired beats wi-fi for anything large, and disabling sleep for the duration removes the most common cause of an overnight upload that isn't there in the morning.