Configuration changes that never appear in Sonarr or Radarr can usually be traced to a problem somewhere between the Recyclarr configuration file and the target application. Incorrect API credentials, unreachable URLs, Docker networking, invalid YAML, or an incorrectly targeted profile can all prevent the expected settings from being synchronized.
Checking the sync output is the quickest way to narrow down the cause. A connection error points toward networking or the application URL, while an authentication error usually indicates an API key problem. A successful sync with no visible changes requires a different approach because the requested settings may already match the configuration or may be targeting another profile or instance.
The troubleshooting steps below cover the main reasons Recyclarr may not sync Sonarr or Radarr and explain what to check before changing your configuration.
Check the Recyclarr Configuration File
The configuration file controls which Sonarr or Radarr instance Recyclarr connects to and which settings it manages. An incorrect value can prevent synchronization or cause changes to be applied somewhere other than the expected instance.
Check the configuration for the correct application URL, API key, instance definition, quality profile, custom formats, and other settings you intend to manage.
Pay particular attention to indentation if you use YAML. A misplaced space can change the structure of the configuration and cause Recyclarr to reject it or interpret it differently.
Recent edits should also be reviewed carefully. If synchronization stopped immediately after modifying the configuration, compare the new section with a known-valid configuration format for your installed Recyclarr version.
Verify the Sonarr or Radarr URL
The application URL must be reachable from the environment where Recyclarr runs.
A local Sonarr installation might use an address such as:
http://localhost:8989
Radarr commonly uses:
http://localhost:7878
Those addresses can cause problems if Recyclarr is running inside Docker. Inside a container, localhost normally refers to the Recyclarr container itself rather than the Sonarr or Radarr container.
A Docker setup may instead require a service hostname such as:
http://sonarr:8989
or:
http://radarr:7878
The correct hostname depends on your Docker Compose configuration and network setup.
Verify the API Key
Recyclarr needs valid API credentials to communicate with Sonarr and Radarr.
Open the application settings and compare the API key with the value stored in your Recyclarr configuration.
An API key can become invalid after it is regenerated. If you changed or reset the key in Sonarr or Radarr, update Recyclarr with the new value.
Avoid copying additional spaces or characters into the configuration. A URL can be completely correct while synchronization still fails because the API key is incorrect.
Confirm Recyclarr Is Reading the Correct Configuration
Multiple configuration files can make troubleshooting confusing.
You may edit one file while Recyclarr is actually using another. This is especially common with Docker installations where a host directory is mounted into a different path inside the container.
Check the command used to start Recyclarr and confirm which configuration directory or file it accesses.
Also check:
- Docker volume mappings
- Working directories
- Configuration paths
- Scheduled commands
- Environment variables
- Container mounts
A configuration change cannot affect synchronization if Recyclarr never reads the modified file.
Run a Manual Synchronization
A manual sync can separate a Recyclarr configuration problem from a scheduling problem.
Run the synchronization command used by your installation and examine the output rather than only checking Sonarr or Radarr afterward.
The output may reveal:
- Connection failures
- Authentication errors
- Invalid YAML
- Missing configuration
- API errors
- Profile problems
- Custom format issues
- Successful synchronization with no required changes
Manual execution is particularly useful when automatic synchronization appears to be doing nothing.
Review the Sync Output Carefully
The terminal output can tell you whether Recyclarr actually reached Sonarr or Radarr.
A connection-related error usually points toward an incorrect URL, Docker networking issue, firewall restriction, or unavailable service.
An authentication-related error points more toward the API key or access configuration.
A successful sync without visible changes is different. It may mean that the requested configuration already matches the current settings.
Read the complete output before making changes. Changing several settings at once can make the original cause harder to identify.
Check the Quality Profile
Quality profiles are a common source of confusion.
Recyclarr may be configured to manage a particular quality profile while you are checking another profile in Sonarr or Radarr.
Verify the profile name and make sure the configuration targets the intended profile.
Also check whether the profile exists in the target application. A renamed or deleted profile can cause the expected configuration to be missing.
The same applies if you have multiple Sonarr or Radarr instances. Make sure the URL and profile combination points to the server you are actually checking.
Check Custom Formats
Custom formats may already exist in Sonarr or Radarr, so a synchronization run does not necessarily mean that a new entry will appear.
Recyclarr can manage existing custom formats according to its configuration. If the format already contains the expected settings, there may be no obvious visual change after synchronization.
Check the custom format itself and its relationship with the quality profile.
If the format is present but its score or profile assignment is incorrect, inspect the relevant Recyclarr configuration instead of assuming that the entire synchronization process failed.
Validate YAML Syntax
YAML configuration files depend heavily on correct indentation and structure.
A configuration can look correct at first glance but still contain a structural mistake.
Common problems include:
- Incorrect indentation
- Misspelled property names
- Missing values
- Incorrect nesting
- Invalid list formatting
- Unsupported configuration options
A problem introduced during a recent edit should be one of the first things you investigate.
Do not copy configuration examples blindly from older tutorials. Recyclarr configuration options can vary between releases, so examples should match the version you are using.
Check Your Recyclarr Version
Version differences can explain why an older configuration suddenly stops working.
If you upgraded Recyclarr recently, review the configuration against the documentation for the installed version.
Older examples may use options, structures, or behaviors that do not apply to your current release.
Check the installed version before modifying a working configuration based on a random example from a forum or old guide.
Check Sonarr and Radarr Versions
The target applications should also be considered if synchronization suddenly stops after an update.
Check whether Sonarr or Radarr was recently upgraded and inspect its logs for API-related errors.
Do not immediately downgrade or change several components. First establish whether the application is accessible and whether its API is responding to Recyclarr requests.
A working connection combined with successful API requests provides a much narrower troubleshooting path.
Check Docker Networking
Docker networking is one of the most important areas to investigate when all three applications run in containers.
Recyclarr must be able to reach the Sonarr or Radarr container over the configured Docker network.
For example, a configuration using:
http://sonarr:8989
requires the sonarr hostname to resolve from the Recyclarr container.
The same principle applies to:
http://radarr:7878
Check that the containers are connected to the appropriate network and that the expected ports are available.
A URL that works from your desktop browser does not necessarily work from inside the Recyclarr container.
Check Reverse Proxy Configuration
A reverse proxy can add another layer between Recyclarr and Sonarr or Radarr.
If you access Sonarr or Radarr through a domain, proxy, authentication layer, or HTTPS endpoint, verify that Recyclarr can use that same route.
Problems can occur because of:
- Incorrect proxy routing
- DNS resolution
- TLS configuration
- Firewall rules
- Authentication requirements
- Incorrect paths
Testing the direct application address can help determine whether the reverse proxy is responsible.
Check API Access Restrictions
Additional access controls can prevent Recyclarr from reaching the API even when the application works normally in a browser.
For example, a reverse proxy may require authentication before allowing requests through to Sonarr or Radarr.
The API key configured in Recyclarr does not automatically satisfy unrelated authentication requirements imposed by another service.
Review any proxy, firewall, authentication, or access-control rules between Recyclarr and the target application.
Inspect Recyclarr Logs
Detailed logs are often the fastest way to identify the actual failure.
Look for messages containing terms such as:
error
warning
failed
connection
authentication
API
configuration
sync
The exact error matters.
A timeout suggests a connectivity problem. An authentication failure suggests credentials or access restrictions. A configuration parsing error points toward the Recyclarr configuration file.
Avoid treating all sync failures as the same problem.
Check Sonarr or Radarr Logs
The target application logs can provide another side of the story.
If Recyclarr says it is making API requests but the expected changes are not appearing, check Sonarr or Radarr logs around the same time.
You want to determine whether the application:
- Received the request
- Rejected the request
- Returned an API error
- Accepted the request
- Made no relevant change because the configuration already matched
Comparing both sides can quickly identify whether the problem occurs before or after the request reaches Sonarr or Radarr.
Check Docker Volume Permissions
File permissions can cause unexpected behavior in containerized installations.
Confirm that the Recyclarr container can access its configuration and required data directories.
A configuration file that is readable but associated directories that cannot be written to can create problems depending on the operation being performed.
Check the mounted paths, ownership, and permissions if the issue started after recreating or migrating your container.
Check Environment Variables
Environment variables may provide or override configuration values depending on how your installation is structured.
Review your Docker Compose file, container environment, and secret configuration if you recently changed them.
An incorrect environment variable can result in Recyclarr connecting to a different server or using credentials different from those you expect.
Check the configuration actually available to the running container rather than relying only on files stored on the host.
Restart Recyclarr After Configuration Changes
A persistent Recyclarr process may need to be restarted after certain configuration or environment changes.
Restarting the Recyclarr container or service ensures that the current configuration is loaded by a fresh process.
However, restarting should not replace troubleshooting. If the problem remains, inspect the logs immediately after startup and during the next sync attempt.
Check Automatic Scheduling
Manual synchronization and automatic synchronization should be treated as separate troubleshooting cases.
If a manual sync works correctly but scheduled syncs do not, the configuration and API connection are probably not the main issue.
Check the scheduling mechanism for:
- Disabled schedules
- Incorrect commands
- Incorrect configuration paths
- Stopped containers
- Permission problems
- Failed scheduled jobs
A scheduler can fail even though Recyclarr itself is configured correctly.
Confirm the Correct Instance
Multiple Sonarr or Radarr instances make it easy to inspect the wrong server.
For example, you might have separate instances for different libraries or environments.
Confirm that the URL in Recyclarr points to the same Sonarr or Radarr instance you are checking.
This simple check can prevent unnecessary changes to an otherwise working configuration.
What If Recyclarr Reports a Successful Sync?
A successful synchronization does not necessarily mean that you will see a new or obvious change in Sonarr or Radarr.
The requested settings may already be correct.
For example, a custom format may already have the expected conditions and score. A quality profile may already contain the desired configuration. Recyclarr can therefore complete the synchronization without producing a visible difference.
Compare the current application settings against the values defined in your Recyclarr configuration.
Also verify that you are checking the correct profile and instance.
What If Nothing Changes After Editing the Configuration?
Start by confirming that Recyclarr is loading the edited file.
This is particularly important when using Docker. A host directory may not be mounted to the path you expect inside the container.
After confirming the file path, validate the configuration and run a manual sync.
If the output still does not reflect your changes, inspect the exact configuration loaded by the running Recyclarr environment and review any relevant errors.
Quick Troubleshooting Checklist
Use this checklist before rebuilding or reinstalling Recyclarr:
- Confirm Recyclarr is running.
- Confirm the correct configuration file is being loaded.
- Verify the Sonarr or Radarr URL.
- Verify the API key.
- Check Docker networking if applicable.
- Validate the YAML configuration.
- Confirm the target Sonarr or Radarr instance.
- Check the intended quality profile.
- Check custom format configuration.
- Review Recyclarr logs.
- Review Sonarr or Radarr logs.
- Run a manual synchronization.
- Check the installed Recyclarr version.
- Check recent Sonarr or Radarr updates.
- Test automatic scheduling separately.
Frequently Asked Questions
Why does Recyclarr connect to Sonarr but make no changes?
The requested settings may already match the configuration defined in Recyclarr. Check the sync output and compare the target quality profile and custom formats with your configuration.
Why does Recyclarr work manually but not automatically?
A working manual sync usually indicates that the basic configuration and API connection are functioning. Check the scheduler, scheduled command, configuration path, and container state.
Why does Recyclarr fail to connect to Sonarr in Docker?
The URL may be using localhost, which points to the Recyclarr container rather than the Sonarr container. Check the Docker network and use the appropriate service hostname when required.
Can an incorrect API key stop Recyclarr from syncing?
Yes. Recyclarr needs valid API access to communicate with Sonarr and Radarr. A regenerated or incorrectly copied API key can prevent synchronization.
Why are my Sonarr quality profiles not updating?
Check that the intended profile exists and that the Recyclarr configuration targets the correct profile and Sonarr instance. Also review the sync output for configuration or API errors.
Why are my Radarr custom formats not appearing?
Check whether the formats already exist, whether the correct Radarr instance is being targeted, and whether the custom format configuration is included in the synchronization process.
Can a Recyclarr version change break my configuration?
Yes. Configuration examples and supported options can differ between releases. Compare your configuration with documentation appropriate for the Recyclarr version you have installed.
Where should I look first when Recyclarr synchronization fails?
Start with the Recyclarr sync output. It can quickly indicate whether the problem involves configuration parsing, connectivity, authentication, or the target application’s API.
Conclusion
Recyclarr synchronization problems are usually easier to diagnose when the process is checked from one end to the other. Start with the configuration file, verify the Sonarr or Radarr URL and API key, and then confirm that Recyclarr can reach the correct application instance.
Docker networking, YAML errors, quality profile targeting, custom formats, version differences, and scheduling can all produce different symptoms. Reviewing Recyclarr logs together with Sonarr or Radarr logs provides useful evidence about where the synchronization process is failing.
A manual sync is also an important test. If it succeeds, focus on the scheduled execution. If it fails, use the error message to narrow the problem to configuration, authentication, networking, or the target application’s API.