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Common Turnitin Similarity Index Errors and Issues

The following are common errors and issues seen when hovering over the similarity index error icon in ManageBac Deadlines and Tasks with dropbox and Turnitin enabled.

  1. Due date has passed and Late Submissions are not allowed
  2. Assignment Line Item not found
  3. Class Expired
  4. Other Common Issues

Late Submissions are not allowed

A black triangle with exclamation point indicates an error in generating a Similarity Index for the file uploaded. Click the Feedback Studio button to access the Turnitin Feedback Studio for this Deadline and ensure that this deadline accepts late submissions.

In the Feedback Studio Assignment Inbox, click Settings > Optional Settings access the Turnitin Assignment settings explained in detail here.

Tick the box to allow late submissions and click Submit at the bottom of the page.

Navigate back into the ManageBac Deadline or Task page and click the Submit Coursework to Turnitin button to resubmit the file to Turnitin servers. Though the index will not be automatically visible, you can access the Feedback Studio Assignment inbox again to see the Similarity Index generated.

The Similarity Index will be shown in the ManageBac Deadline or Task Dropbox once you reopen the Deadline or Task Dropbox from the Calendar or Tasks page in ManageBac.

Assignment Line Item not found

There are several possible reasons for this error message. The most common is that Turnitin was enabled for the Task or Deadline after the due date.

Tasks and Deadlines created in ManageBac can have Turnitin enabled at any time. But the integration will only work properly if Turnitin is enabled before the due date of the task. If needed, feel free to edit the due date of the Task or Deadline in ManageBac and enable Turnitin at the same time. Then use the Submit Coursework to Turnitin button in the Task or Deadline dropbox to resubmit files already submitted to Turnitin servers and generate a Similarity Index.

Other possible reasons for the assignment line item not found message include incorrect credentials for the MB - Turnitin integration. To see a more specific error message, click Feedback Studio.

The integration credentials can be reviewed and edited via Settings > Integrations > Partners > Turnitin.

Once the credentials entered in ManageBac match the Turnitin credentials for your school, you will be able to access the Feedback Studio in the Task or Deadline Dropbox. Please use the Submit Coursework to Turnitin button in the Task or Deadline Dropbox to generate Similarity Indices for the files submitted.

Class Expired

This error message appears for Year Group Deadlines or transitioned two year classes, because in Turnitin all classes are by default set to one academic year duration. Year Groups created in ManageBac also count as classes in Turnitin. The Turnitin admin for your school can extend the duration of classes in Turnitin. Please see further details about this here.

Once the class has been extended in Turnitin, please use the Submit Coursework to Turnitin button in the Task or Deadline Dropbox in ManageBac to generate Similarity Indices for the files submitted.

Other Common Issues

The Similarity Index is very high or 100% but the student has only submitted one file. Especially for assignments or deadlines with a Draft and Final version, it is likely that Turnitin compares the draft and final version against itself and thus generates a high percentage of similarity for the final version. Navigate into Feedback Studio > Settings > Optional Settings when the Task or Deadline was created and adjust where submitted files are stored or what they are compared against.

It would be possible to not store the draft assignment in the paper repository and therefore not have the final version compare against an earlier copy of itself. It would also be possible to not compare against the student paper repository at all and thus not create a high similarity index.

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