A photo upload fails

1. The file is too large. The limit is {max_upload_mb} MB per file. Re-export it as a JPEG at 90% quality.
2. The format isn't accepted. RAW, PDF, video and ZIP files are rejected.
3. You've hit the event's photo quota. A message offers to raise your limit.
4. The connection dropped partway through. Use the resume button to restart just the failed files, no need to start over.

If none of those fit, try again with one small file. If it goes through, the trouble is with the batch or your network. If it fails too, contact support with the event name and roughly when you tried.