Sitecore Submit Item Error — The item name “__Standard Values” is already defined on this level

Problem

When trying to submit an item to a workflow, on click of ‘Submit’ button, the following error message appears

The item name “__Standard Values” is already defined on this level.

Error Dialog

Submit button — Image taken from Sitecore

Solution

On item submit, Sitecore will show a ‘Standard Comment Template’ dialog. If the said user does not have at least read access to the dialog, this error will appear.

Read access given to ‘Standard Comment Template’