Search on OTTR docs

Search on the OTTR docs for what you are looking for. Note that first few entries are sponsored, the actually helpful stuff will be below that.

Most Common Errors

This guide will describe the most common OTTR errors and pitfalls and how to address them. When you open a pull request, you should see a report like this:

When you see an ❌ , click on the Details button to see the error message. We’ll discuss the most common error messages here.

file is not in PNG format: Google Slides permissions fail

Error example:

Error in png::readPNG(path, native = TRUE, info = TRUE) :
  file is not in PNG format
Calls: local ... lapply -> FUN -> raster_dpi_width -> attr -> <Anonymous>
Execution halted
Error in Rscript_render(f, render_args, render_meta, add1, add2) :
  Failed to compile <file_name>.Rmd
Calls: local ... <Anonymous> -> render_new_session -> Rscript_render
Execution halted
Error: bookdown::render_book() failed to render the output format 'bookdown::gitbook'.
Execution halted

What does this mean?:

Your Google Slides presentation you have tried to retrieve a slide from with ottrpal::include_slide() is not public. Your Google Slide document must be set to Anyone with a link. See this article for more details. The renders will fail if this is not set! See the setting up images and graphics section for more details.

Process completed with exit code 1.: Spell check/url check/quiz format fail:

Underneath a section that says something like: **Check spelling/url/quiz errors - fail if too many of them** you may see something like:

Run exit 1
  exit 1
  shell: sh -e {0}
Error: Process completed with exit code 1.

This is failing on purpose – it means that checker has found errors. Return to your pull request page and look for a comment that says something like:

⚠️ There are <spelling/quiz/url> errors that need to be addressed. Read this guide for more info.
Download the errors here.
Comment updated at <some_date> with changes from <commit>

Click on the Download the errors here to see the list of errors and which files they were found in. For help in addressing these errors, click on the Read this guide for more info button.

CONFLICT (modify/delete): Merge conflict fail:

Error example:

CONFLICT (modify/delete): <file_name> deleted in <branch_name> and modified in HEAD. Version HEAD of <file_name> left in tree.

This will often happen when render-preview’s git handling doesn’t know which changes you are looking to preview. The easiest way to fix this problem is to create a separate pull request that completely deletes the files lists. To do this, follow these steps:

  1. Take note of your pull request’s number. Go to the pull request page and see what #number is posted there.
  2. On your GitHub repository, go to Code and click on Branches.
  3. Your pull request’s preview is made on a branch named preview-<number of your pull request>. Find this branch and click the trash can icon. This will delete the preview branch and hopefully get rid of this error. Read this for more info on how to delete a branch.
  4. Re-trigger your GitHub actions run and it should pass.

Parser error: while parsing a flow sequence: _bookdown.yml parse error

If you see an error like this:

Run Rscript -e "bookdown::render_book('index.Rmd', output_format = 'all')"
Error in yaml::yaml.load(..., eval.expr = TRUE) :
  Parser error: while parsing a flow sequence at line 4, column 12 did not find expected ',' or ']' at line 11, column 13
Calls: <Anonymous> ... <Anonymous> -> resolve -> <Anonymous> -> yaml_load -> <Anonymous>
Execution halted
Error: Process completed with exit code 1.

It means that the formatting in your _bookdown.yml is off. If you forget a comma, or quote, or a ] this message will appear in the github actions preview run.

Take a careful look at the _bookdown.yml. Keep in mind that _bookdown.yml rmd_files spec should look like this (indents, quotes, and commas included in this pattern):

rmd_files: ["index.Rmd",

Commit the changes to your _bookdown.yml and see if the preview GitHub action runs appropriately.

Ask a question on the Google Group

You can always start a discussion on the Discussions tab above. You can also join our Google Group to ask questions and keep in touch with the OTTR community.

To join the Google Group:

  • Go to
  • Click “Ask to join group”. You need to be signed in to a Google account.
  • You will be prompted for some information, such as your display name and your subscription preference. We recommend subscribing to “Combined updates” to avoid flooding your inbox, but you can always change this later.

To start a discussion:

  • Click on “New conversation”.
  • Provide a relevant subject and as much detail as you can about your problem/concern/idea.
  • Click “Post message”.

Remember that everyone can see your post. This is a good thing because if you need help, chances are someone down the line will too. This public forum ensures the next person can figure things out!

Your feedback is greatly appreciated! You can fill out this form
or file a GitHub issue.

Otter images by Jimin Hwang.