Media sync fails with "error sending request for url ()" while collection sync succeeds

Anki Syncing & AnkiWeb
1

Hi, I’m having an issue with Anki media syncing on my Mac. My collection itself syncs successfully to AnkiWeb, but immediately afterward the media sync fails with:

A network error occurred.
Error details: error sending request for url ()

My setup:

  • Anki 26.09.2 (bb0dd6d1) (ao)
  • macOS 26.7, Apple Silicon
  • Python 3.13.15
  • Qt 6.11.2 / PyQt 6.11.0
  • Local collection.media folder: ~13.3 GB, 101,043 items
  • AnkiWeb reports ~12,022 MB of media
  • Tools → Check Media reports 396 missing files and 29,786 unused files

When “Synchronize audio and images too” is disabled, syncing works normally and I get “Collection sync complete” with no error. When I enable audio/images, the collection sync still completes successfully, but the network error occurs shortly afterward during media syncing.

Troubleshooting I’ve already tried:

  • Restarted Anki and Mac
  • Logged out of AnkiWeb and back in
  • Tried normal Wi-Fi and a phone hotspot
  • Disabled add-ons / launched Anki without add-ons
  • Tools → Check Database (completed successfully)
  • Updated macOS from 26.6.2 to 26.7
  • Confirmed no VPN, proxy, firewall, or iCloud Private Relay is interfering
  • Confirmed sync.ankiweb.net and sync3.ankiweb.net are reachable over HTTPS from Terminal
  • Created a separate clean Anki profile and successfully synced it with AnkiWeb
  • Quit Anki and renamed collection.media.db2 so Anki could rebuild the media database; Anki rebuilt it successfully, but the same media-sync error remains

This started after I attempted to set up AnkiHub earlier in the day. I am no longer using AnkiHub. My main collection and local media appear intact.

I also use AnkiMobile. It currently requires a full sync, and an accidental Upload attempt from the phone eventually timed out. I checked AnkiWeb afterward and my decks/cards still appear normal.

Since collection syncing works consistently and the error only occurs when media syncing is enabled, is there a way to obtain a more detailed media-sync log or determine which media request/file is causing the failure? I would prefer not to delete or reset my local media because the collection contains a large amount of AnKing media.

Thanks!

2

As a first step, Delete Unused Media from that screen, so Anki stops trying to sync those 29K unnecessary files. If the file causing the problem is one of those, then that will solve it.