I have a Flexi task in a workflow and I want to edit the form, but when i click on Edit Task Form>Edit with Nintex Forms nothing happens, it load for like 2 seconds and then nothing opens. I also tried Edit Task Form>Edit with InfoPath and same thing... nothing loads.
This feature was working before, it just all of a sudden stopped working.
I figured it out.
Under Site Collection Features, i deactivated "Nintex Forms for Nintex Workflow" and activated it back. Fixed the issue.
All the customizations on the form will be lost if you reset the feature, always have a backup copy of your workflow forms. This happened to one of our list workflow. It seems sometimes the form gets disassociated with the action on the workflow.
Nitin, I found that you can just backup the workflow itself and the forms will also be backed up inside the same workflow backup file. Related thread: Edit Start Form button not working
i went through the same issue, De-activating and Re-Activating the "Nintex Forms for Nintex Workflow" feature, didnt do any thing.
as a work around, i found if I export the workflow then import the nwf file again to the same list, the edit form option is working as expected.
hope this may help as well