Troubleshoot captions-related issues

This article covers the most common issues you may come across when attempting to upload or playback caption and/or subtitle files. 

In this article:

• Uploading
  • Unexpected Text Track Upload Type
  • Invalid Caption File
• Playback
• Replacing and deleting files

Uploading

If you encounter an error while uploading subtitles or captions to the website, please ensure that you are uploading a file type that we support (SRT, WebVTT, DFXP/TTML, SCC, and SAMI). You may get one of the two following error messages if you try to upload a file type that we don’t accept (ex. “.txt” or “.csv”), or if you have formatting issues within your file (ex. HTML code or improper syntax).

Unexpected Text Track Upload Type

If you receive the “Unexpected Text Track Upload Type” error, double-check to make sure that you are uploading a file type we accept (SRT, WebVTT, DFXP/TTML, SCC, or SAMI). After converting your document to an accepted file type, try uploading it again.

Invalid Caption File

If your file type is one of the supported file types, and you still receive the “Invalid Caption File” error message, please follow these troubleshooting steps to get your file ready to upload.

First, if you are using a DFXP/TTML, SCC, or SAMI file please convert it to a WebVTT file as this file type is the easiest to troubleshoot. Files can be converted using the Caption and Subtitle Format Converter. 

If you are using an SRT file, please convert it to a WebVTT file using the TextEdit (Mac) or Notepad (PC) application. You can follow these steps to convert your file:

• Add the header WEBVTT followed by a line break at the top of the file.
• Find (ctrl-F/cmd-F) the comma character (,) and Replace-All with the period character (.)
• Copy-and-paste the content of the WebVTT file into this validator: Live WebVTT Validator or use Happy Scribe for SRT files (without converting them to WebVTT format).
• Make the appropriate changes for any errors the validator reports back.

Here are some examples:

In this example, the “cue identifier” is the beginning timestamp and the ending timestamp. An error will be registered in the file if you add a line break after the timestamps.

The beginning and ending timestamps must be written on the same line of text or you’ll see an error like the first one displayed in red above.

Additionally, the ending timestamp for a cue should not precede the beginning timestamp or you’ll see the second error message.

Finally, the beginning timestamp for a cue should not be equal to or earlier than the ending timestamp of the preceding cue. In the example above, the ending timestamp for line 3 is the same as the opening timestamp for line 4 (00:18.000), resulting in the error message.

Playback

If your subtitles or captions don’t appear during playback, make sure you’ve activated the caption file by toggling it on. You can toggle on the file by clicking the CC button underneath the video. Once it's blue, the file has been activated.

If your file is active and you’re still not able to see your subtitles/captions, or if they are not showing as expected, please try these troubleshooting tips.

1. First, download the file from the video’s settings page.
2. If you get a 404 Not Found error, the file was invalid and not accepted by the system.
3. If you are able to download the file from the system, convert the file into a WebVTT file using the directions above. Then, paste the content of the file into the validator site. 
4. Once you've done that, make the appropriate changes in your document for any errors the validator reports back.

We recommend using TextEdit (Mac) or Notepad (PC) to make updates to your document. Here are some examples of common issues we’ve come across with subtitle/caption files:

Replacing and deleting files