DOI failed to deposit in OJS

Describe the issue or problem
Please tell us what happens and what you expected to happen.
We are having problem in getting few of our articles DOI and getting error :Failed Ajax request or invalid JSON returned.We have tried to deposit 15 articles , 7 got activated ,8 were failed to get activated with above error. We have contacted Cross ref support and they have directed us to contact OJS for that. Can anyone please guide us to resolve this issue.

Steps I took leading up to the issue
For example:

  1. Go to ‘…’
  2. Click on ‘…’
  3. Scroll down to ‘…’
  4. See error

What application are you using?
For example, OJS 3.3.0-4

Additional information
Please add any screenshots, logs or other information we can use to investigate this problem.

Hi @Bilal

You can see whether the XML file created by OJS to register DOI for journal articles has been successfully sent to the Crossref system, and if so, what error occurred, as follows:

  1. Go to and login with Crossref username and password

  1. At home tab, click Submission Administration

  1. To find the records where the error occurred, select the time period in which the registration attempts were made retrospectively, and click “Has Error” option

  1. In the result page, click the ID number of the record that you want to investigate,

  1. You can find more information in the stack trace form with error logs, as in the image below.

If you find no results when you search for failed records, the record files may have never been submitted to the Crossref system.