We have created a two level custom approval workflow on (an InfoPath) form library using SharePoint Designer (SPD) with first and second approver. The workflow works fine as long as the approver is in the Site Collection Administrators group. The approvers
who are not in the admin group can get to the custom Task form for approve/reject, but they can only view the form. When they click on the “Edit Item” button of the task list item, they receive “Access Denied” error. We have given these
approvers “Approve”, “Contribute” permissions on the Form library and even Full Control on the task form list (all items). Note: The users use their domain account and the error they are getting is: Access Denied, You are currently
signed as DomainName\LoginName, Sign in as a different user.
We have read through several forums and have found people having the same issue. We tried all of the suggestions described in the following links - but no success so far.
SharePoint Designer Workflows, Tasks, and the Annoying “Access Denied” Error
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