Paperless-ngx: Troubleshooting Re-Consumption Of Deleted Files

Understanding the Issue: Paperless-ngx and Deleted Files

Paperless-ngx users often rely on the consume folder to import documents. This process usually works smoothly, but sometimes, issues arise where files get stuck in a loop. Specifically, files appear in both the "failed" and "complete" tabs within the file tasks. This indicates a problem where Paperless-ngx attempts to process a file, succeeds initially, deletes the original, and then encounters an error trying to re-consume the now-deleted file. This can be frustrating because it suggests that the system is trying to process a file that no longer exists, leading to confusion and potential data integrity concerns. The provided logs give us insights into what is going on. Examining the webserver logs reveals a clear sequence of events. The system successfully adds the file to the task queue, processes it using OCR (Optical Character Recognition), and generates a thumbnail. It then saves the record to the database, assigns a document type, and deletes the original file along with its working copy. Immediately following this successful process, the system throws an error stating that the file cannot be consumed because it is not found. This sequence is a key indicator of the underlying problem: Paperless-ngx is attempting to re-consume a file it has already successfully processed and deleted. To understand the root cause, one must delve into the Paperless-ngx configuration and the file handling processes to identify the source of this re-consumption attempt.

Steps to Reproduce and Log Analysis

Reproducing this issue involves placing a PDF file into the consume folder. The issue manifests because after the initial successful processing and deletion, the system tries to re-consume the same file. The web server logs are essential for diagnosing this issue. The logs provide a detailed timeline of events, from adding the file to the task queue to the final ConsumerError. The logs show the successful processing of the file, including OCR, thumbnail generation, database saving, and file deletion. Following the deletion, the logs display the error message: "Cannot consume /usr/src/paperless/consume/scan_2025-10-26_174024.pdf: File not found." This error indicates that the Paperless-ngx system attempts to process the deleted file again, failing because the file no longer exists in the specified location. This behavior suggests a configuration problem or a bug that triggers an unwanted re-consumption attempt. Troubleshooting requires a methodical approach, starting with the logs to pinpoint the exact sequence of events, followed by inspecting the configuration settings and any custom scripts or integrations that may be involved in the document handling process. Understanding this step helps in identifying any potential triggers that cause the system to re-attempt the consumption of already-processed files.

Webserver Logs and Error Analysis

The webserver logs are critical for understanding the sequence of events and identifying the error. The logs reveal that the initial file processing completes successfully, and the original file is deleted as part of the normal workflow. The error occurs when the system attempts to process the same file again, but the file is no longer available. The ConsumerError is the core of the problem, indicating that the consumer preflight plugin has failed. This failure occurs because the file is not found. This points towards a problem in the task queue or a process that incorrectly re-adds the deleted file for processing. It is vital to examine the configuration settings related to the consume folder and task management. Check the settings to ensure that the system is not configured to re-process files after initial consumption. Additionally, review any custom scripts or integrations that could be unintentionally adding files back into the processing queue. Analyzing the logs helps in identifying the exact point where the re-consumption is triggered and provides clues about the underlying cause of the problem.

System Environment and Troubleshooting

The user's environment is based on TrueNAS SCALE 20.04 and uses the "Appstore" installation method. The version of Paperless-ngx is 2.19.2. Troubleshooting steps should include checking the Paperless-ngx configuration for any settings that might cause files to be re-processed after successful consumption. Verify the settings to ensure the system does not re-process files after the initial consumption. Furthermore, inspect the task queue to determine if any tasks are persistently queued for the deleted files. Review the configuration files and the settings within the Paperless-ngx interface to identify any potential misconfigurations. Considering the installation method, check if any automated scripts or processes are running within the TrueNAS environment that could be triggering the re-consumption attempts. Reviewing the TrueNAS configuration and app settings is crucial to identifying any external factors that affect Paperless-ngx. By systematically examining these areas, one can pinpoint the root cause of the problem and implement a solution. The aim is to ensure that the system does not try to process files that have already been handled and deleted successfully. This approach involves careful inspection of the settings, log analysis, and system environment checks to identify and resolve the issue.

Potential Solutions and Recommendations

To resolve this issue, you must identify the cause of the re-consumption attempts and prevent them. The first step involves checking the Paperless-ngx configuration for any settings that might trigger re-processing. Inspect the settings related to the consume folder and task management to ensure that files are not being re-added to the queue. Next, examine the file tasks within Paperless-ngx to see if any deleted files are persistently listed. If so, investigate why these tasks are not being removed. It's also important to check for any custom scripts or integrations that could be contributing to the issue. These scripts might inadvertently re-add files to the consume folder or trigger the processing again. Consider reviewing any custom scripts or integrations that could be re-introducing the files into the processing queue. Finally, ensure that the Paperless-ngx version is up to date, as the issue might be addressed in a newer release. If the problem persists, review the TrueNAS configuration and application settings for any external factors that might be causing the re-consumption. By systematically checking these areas, you can pinpoint the root cause and implement the appropriate fix. This may involve adjusting the configuration, disabling problematic scripts, or updating the software to resolve the issue effectively.

For further assistance and community support, you can visit the Paperless-ngx GitHub repository.