Identify which output FFmpeg tried to open
Read the command or sanitized application log from the start of the failed attempt. FFmpeg accepts an output URL after the input and output options: a local path or file: URL is different from rtmp:// or rtmps://. If one process writes both a recording and a stream, identify the output named immediately before the fatal line rather than guessing from the last line alone.
- Record the output type and account/room label, but redact the full stream key and any URL credentials.
- Keep the first meaningful error before the final “Error opening output files” line.
For RTMP output, check the current session and connection
When the failed destination is RTMP or RTMPS, verify that the official platform currently provides that route and that the server URL and key belong to the same active session. Check the earlier FFmpeg message for resolution of the host, connection refusal, timeout, authentication or handshake failure, then examine network stability. A connected or retried process does not guarantee the public LIVE started.
- Do not repeatedly reuse a key from a closed or recreated room.
- Check the official room state and a separate viewer page after the connection is restored.
For a local file, check the path and storage
When the failed destination is a disk path or file: URL, confirm that its parent directory exists, the process can write there, the volume is mounted and has free space, and another process or permission rule is not blocking the file. Test with a harmless short local output in an approved location; do not change the streaming target while diagnosing a file error.
- Use the actual process user and destination path for permission checks.
- A local write failure alone says nothing about TikTok account permissions.
Collect evidence before changing settings
Preserve the FFmpeg version, time, redacted command/output URL, all lines just before the failure and whether any frames were sent. FFmpeg’s documentation describes loglevel and report options, but a full report can contain command-line secrets: redact credentials before sharing it. Add the current platform room status for RTMP incidents or the disk/path result for local output, then change one factor and retry a bounded test.
- Do not paste complete RTMP URLs, stream keys, cookies or tokens into tickets.
- If multiple outputs are configured, record which one failed and whether the other succeeded.
FAQ
Frequently asked questions
Start here for common questions about purchasing, access and system requirements.
Does “I/O error” mean my disk is full?
No. It can also occur while opening an RTMP network output. Inspect the destination and preceding error; check disk space only when a local output is involved.
Can I tell from the final fatal line that TikTok rejected my stream?
No. The earlier FFmpeg messages and the official LIVE state are needed to distinguish network, session, authorization and local-output failures.
REFERENCES
References
Content reviewed: October 13, 2026 · TKLive product team