An interrupted asynchronous video workflow can cause a Loom recording to hang indefinitely with a Processing status stuck at 0%. This processing failure halts communication loops whether you are using the Chromium web extension or the desktop client application. The issue occurs when the background assembly file corrupts, or when a localized network drop blocks the server from receiving the initial index block.
Fast-Fix: The 45-Second Solution
A Loom video stuck at a 0% processing loop is typically caused by a corrupted local manifest file or an interrupted multi-part upload stream that prevents Loom’s cloud servers from stitching the video segments together. To resolve this immediately, force-close the Loom client, clear the application’s local indexing cache, and trigger a manual upload recovery from the desktop client’s troubleshooting menu.
Quick Logic Snapshot
- Severity: Operational (Prevents video file sharing and cloud compilation)
- Impact: Single User / Affected Recording File
- Primary Cause: Missing or out-of-order video chunk uploads that cause the cloud rendering engine to wait indefinitely for the starting data block.
- Rare/Security Cause: Local SSL packet inspection engines or corporate web filters stripping metadata headers from outgoing HTTPS payloads.
Low Risk vs. High Risk Scenarios
- Short Browser Recordings (Lower Risk): If a brief screen recording hangs at 0%, the issue is usually fixed by clearing the local browser storage or restarting the extension. The raw file segments are often still cached safely within your browser’s temporary directory.
- Long Desktop App Recordings (Moderate Risk): When a long presentation or product demonstration hangs at 0%, it indicates a sync failure between your hard drive and the cloud ingestion server. This requires manual recovery of temporary files from the local application storage.
- Tenant-Wide Processing Halts (High Risk): If every user across a corporate network experiences a 0% processing freeze simultaneously, the issue is systemic. This points to a global firewall rule blocking outbound binary streams or a major backend outage on Loom’s cloud rendering infrastructure.
What This Means
Think of Loom’s recording pipeline like a modular cargo train. Instead of waiting until your presentation ends to send one massive video file over the internet, Loom breaks your video into 5-megabyte segments (chunks) and uploads them continuously while you speak. A separate document called a manifest file acts as the cargo manifest, mapping out the precise order of these chunks so the cloud engine can assemble them correctly.
If your network connection drops for even a fraction of a second when you hit “Stop Recording,” the manifest file or the very first video chunk can arrive at the cloud destination out of order or corrupted. When the cloud stitching server attempts to compile the video, it reads an incomplete instruction set. It cannot start building without block zero, so it waits indefinitely in an open loop, keeping your dashboard progress display frozen at 0%.
Probability Breakdown
- Interrupted Multi-Part Upload Sync: 50%
- Corrupted Local Manifest Cache File: 30%
- Local Web Filter/Proxy SSL Inspection Interference: 15%
- Loom Cloud Transcoding Engine Outage: 5%
Logic Escalators
Specific environmental configurations can make this upload block worse:
- Aggressive Corporate Proxies: Deep packet inspection tools can strip crucial metadata from outgoing HTTP requests, leaving the cloud server with unreadable video data.
- Low Local Disk Space: If your laptop runs out of storage space during a recording, Loom cannot generate the temporary cache files needed to safely store the backup segments.
- Wi-Fi to Ethernet Handoffs: Switching network adapters while a recording is uploading breaks the active secure socket connections, which can stall the upload sequence.
If Ignored: 1 Hour → 1 Day → 1 Week
- 1 Hour: Immediate workflow bottleneck. Critical visual answers, bug reports, or project handoffs are delayed because the share links remain broken.
- 1 Day: Local cache replacement risk. If users try to record new videos over a stalled application state, the local temporary files for the stuck video may be overwritten and lost forever.
- 1 Week: Ghost assets clutter the user dashboard. Stalled 0% placeholders remain stuck in the cloud processing queue, generating confusing error indicators across shared team folders.
Confused With / False Positives
Do not mistake a 0% processing loop for these distinct issues:
- Loom Cloud Sync Delays: This is a network-side delay where the video has uploaded completely but takes longer to appear due to platform traffic. For those symptoms, see Loom “Cloud Sync” delay causing “Media Offline” in Browser.
- Complete Upload Failures: The application explicitly throws a red “Upload Failed” dialog box instead of hanging indefinitely on a 0% circle icon. For troubleshooting this issue, refer to Loom “Upload Failed” after Long Screen Recordings.
- Hardware Transcoding Hangs: The client freezes during the active recording phase before the upload step begins. For those situations, see Troubleshooting: Loom “Hardware Encoding” vs “Software Fallback”.
What To Do Right Now
- Do Not Delete the Video Placeholder: Removing the 0% processing video from your online dashboard will also delete the cloud matching tokens, preventing any future data recovery.
- Check Loom’s Cloud Status Page: Before changing any local system configurations, verify that Loom’s ingestion and transcoding microservices are operating normally.
- Initiate Desktop App Recovery: In the Loom desktop application, navigate to Preferences > Troubleshooting and click Check for Stuck Uploads to force the app to scan its local cache for unsubmitted video chunks.
- Clear Browser Extension Storage: If you are using the Chrome extension, open the extension settings, clear its local cache, and keep the target tab open to allow the background worker scripts to retry the upload stream.
Immediate Intervention Flags
- Stop recording any new clips if you have an important video stuck at 0%; adding more data to the local cache folder can cause the application to overwrite the cached video segments you are trying to save.
- Stop your troubleshooting steps if the local Loom directory size reads 0 bytes, which indicates that the local raw recording files were never saved to your hard drive.
- Stop running clean-up utility scripts or third-party optimization tools, as they may delete the temporary directories where your unstashed video segments are located.
What a SysAdmin Will Check
An administrator will track down the failure by opening the browser’s developer console or looking at the Loom desktop application log files located in %APPDATA%\Loom\ on Windows or ~/Library/Application Support/Loom/ on macOS. They will filter the log output for HTTP 403, 409, or 502 status codes occurring during multi-part upload attempts.
The administrator will check if outbound rules in the company firewall are dropping long-lived secure connections or flagging high-volume PUT requests to Loom’s cloud storage buckets. Finally, they will verify that web security software is not modifying the authentication headers that connect the local client to the cloud ingestion engine.
Administrative Scope
- Minor (User-level): An isolated network interruption has stalled the upload queue. This can usually be resolved by triggering a manual upload retry or clearing the browser cache.
- Moderate (Team-level): A bad software version or browser update breaks the multi-part upload tool across a group of users. This requires updating the Loom application or extension to the latest build.
- Major (Tenant-wide): A change to corporate firewall rules blocks binary file transfers across the entire organization. Fixing this requires modifying your corporate web filtering profiles.
Related Logical Handshakes
Processing anomalies often happen alongside other common capture and synchronization issues. If your video uploads successfully but drops significantly in quality after processing, check out Loom “Resolution Mismatch” (1080p recording showing as 720p). If a recording fails to process because of a total system crash during long sessions, refer to Loom “Upload Failed” after Long Screen Recordings. If your video finishes processing but displays error screens when opened in a standard browser window, you can diagnose the problem using Loom “Cloud Sync” delay causing “Media Offline” in Browser.
Operations Summary
A Loom video stuck in a 0% processing loop is rarely a total loss; it is simply an assembled asset missing its starting pieces. Because the platform uploads videos in continuous segments, the missing parts usually still exist inside your local device storage. Before discarding the clip, use Loom’s built-in recovery options to upload the remaining data chunks manually, or check your local network firewall rules to make sure corporate security systems are not blocking the upload path.