We have document library on which the Nintex workflow is running and assigns a flexi task to an approver. The form is built using Nintex Forms 2013.
This approver form contains lookup controls which are connected to the list columns. So when the user changes the look up value it gets modified in the main list column. However, when an approver tries to open the task assigned to them, they get the below error:
“Sorry, something went wrong
An unexpected error has occurred.
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We have went through the ULS log and found few error entries to Nintex forms as below:
Failed to handle form host page on initialize event. Error: Cannot find the task form. Please check the action's form in the Workflow Designer..
Stack trace: at Nintex.Workflow.Forms.ControlTemplates.TaskForm.3BM=(String 3RM=, FormData 3hM=) at Nintex.Workflow.Forms.ControlTemplates.TaskForm.0RM=() at Nintex.Workflow.Forms.ControlTemplates.TaskForm.vxM=() at Nintex.Workflow.Forms.ControlTemplates.TaskForm.OnInit(EventArgs e) f526259d-3955-70df-1cbe-32c7dfeeebb0
Please note this error is intermittent and there is no proper pattern of occurrence. We have verified the permission and everything looks fine.