When to Retry Failed Jobs

Sometimes Zencoder is unable to successfully complete a job. Typically we will return an error explaining the specific reason a job failed. While the majority of these errors are due to issues with the submitted file, occasionally there are situations where resubmitting a job a second time will achieve a better result.


We strive to handle as many files as possible and to transcode them successfully the first time and generally recommend against resubmitting files that fail. We request that you not repeatedly retry jobs that have encountered the same error twice. Instead, please contact us with the job ID and we'll gladly investigate the file for you. Resubmitting jobs indiscriminately is never advised, and doing so may result in limitations being placed on your Zencoder account.

The reason we ask that you not resubmit all failed files is due of the additional load it places on Zencoder and the resources it consumes. We do not charge for failed jobs, but they fill space on our encoders while we attempt to process them, which can affect our ability to get to other jobs as efficiently as possible. By not resubmitting failed files you help us keep prices down for you while continuing to offer fast, efficient encoding.

When to retry now

Errors To Retry Right Away

If you encounter a TranscodingError or a WorkerTimeoutError, it may be due to an issue with the encoder that was handling the file. It is not unreasonable in these situations to retry the job once more. If the same error is raised on the second attempt, you will better served by contacting us with the Job ID so that we can investigate and get you more information about the cause of the error.

When to retry later

As Zencoder adds support for new codecs and files, we are sometimes able to process files that had previously failed. If any jobs have failed with an UnsupportedCodecError or an UnsupportedEncodingError, they may be processable later if support was added. We announce newly supported formats in our newsletter and on the Zencoder dashboard, so if you see that a codec that Zencoder did not previously support has been added, searching for jobs that encountered these errors will give you a list of files to retry.

AWS outage

In the case of an AWS outage, in some cases jobs are retried automatically and in some cases you must retry the job(s). When an internal issue occurs (such as AWS outage, file transfer failures, etc), jobs are retried automatically.

When a job fails due to something specific to that job (bad or not reachable source file, wrong specified formats, etc), the job will fail and you will be notified the standard way. It is up to you to retry it (for up to 7 days, after which need to start a new job).

File transfer errors

If Zencoder is unable to successfully transfer a file, while either uploading or downloading, you should be making any changes suggested by the error message before retrying the job. You may need to give Zencoder access to your S3 bucket, confirm the provider user exists if passing credentials in the URL, grant public access to the file, or make sure that usernames and passwords in URLs are properly escaped. Once you have confirmed that access to the file is set correctly and that the URL is correct, retry the job.

If you get another error

Any other errors are typically issues with the file itself - the file may be corrupt, not contain any media that we could detect, or be encrypted in a way that we cannot process. Resubmitting these jobs will be highly unlikely to result in a different outcome.

If there are specific files that you come across with other errors than the ones above, which you expect to be handled, you should bring it to our attention rather than resubmitting it. We will review the file and explain why we are unable to process the file, or add support to Zencoder if possible.