Sonarr/Sonarr · warning · DownloadClientUnavailableException

All download clients for {downloadProtocol} are not availabl

Error message

All download clients for {downloadProtocol} are not available

What it means

GetFilteredDownloadClients: at least one client is blocked, no non-blocked clients remain, and filterBlockedClients is true, so every client for the protocol is unavailable. DownloadClientUnavailableException. Transient.

Source

Thrown at src/NzbDrone.Core/Download/DownloadClientProvider.cs:233

                    {
                        throw new DownloadClientUnavailableException($"Indexer specified download client is not available due to recent failures for {indexer.Name}");
                    }

                    return [client];
                }
            }

            if (blockedProviders.Any())
            {
                var nonBlockedProviders = availableProviders.Where(v => !blockedProviders.Contains(v.Definition.Id)).ToList();

                if (nonBlockedProviders.Any())
                {
                    availableProviders = nonBlockedProviders;
                }
                else if (filterBlockedClients)
                {
                    throw new DownloadClientUnavailableException($"All download clients for {downloadProtocol} are not available");
                }
                else
                {
                    _logger.Trace("No non-blocked Download Client available{0}.", forSingleClient ? ", retrying blocked one" : $" for {downloadProtocol}, returning all clients");
                }
            }

            return availableProviders;
        }
    }
}

View on GitHub (pinned to da2284d7ea)

Solutions

Resolve connectivity to the clients (run Test on each in Settings -> Download Clients).
Wait out the cooldown and retry.
Add or re-enable a healthy client for that protocol as a fallback.

Defensive patterns

Strategy: retry

Validate before calling

var blocked = new HashSet<int>(_downloadClientStatusService.GetBlockedProviders().Select(v => v.ProviderId));
var healthy = _downloadClientFactory.GetAvailableProviders()
    .Where(c => c.Protocol == protocol && !blocked.Contains(c.Definition.Id)).ToList();
if (!healthy.Any()) { /* all blocked: defer the grab or alert */ }

Try / catch

try { /* get clients with filterBlockedClients=true */ }
catch (DownloadClientUnavailableException ex) when (ex.Message.Contains("are not available"))
{
    // transient: back off and retry; alert the operator about a possible outage
}

Prevention

Run multiple clients per protocol so one outage does not block all grabs.
Alert when clients enter the blocked state.
Fix shared dependencies (network, credentials) quickly.

When it happens

Trigger: All enabled clients for the release's DownloadProtocol are simultaneously in the blocked-providers set, and the caller requested blocked clients be filtered out.

Common situations: A shared outage (seedbox/tracker down, or a usenet provider outage) knocks out every client of a protocol; misconfiguration causes repeated auth failures across all clients.

Related errors

AI-assisted analysis of Sonarr/Sonarr@da2284d7ea (2026-08-13). Data as JSON: /api/errors/429aa32c1f7091bc. Report an issue: GitHub.