You click Open this Task from a SharePoint workflow on the Outlook ribbon, and the InfoPath workflow approval form opens. Some data may be missing from this form, such as in the Requested By field. When you click any of the buttons on the InfoPath form, such as Approve, Cancel, Reject, Request Change or Reassign Task, they either are not able to be clicked or when you click them you may receive the following error message.
Outlook cannot complete this action, because of an error in the form’s code.
When you click the “Show Details” button on the error dialog box, the following text may appear:
A button in the form template is missing an xd:CtrlId attribute.
Important Follow the steps in this section carefully. Serious problems might occur if you modify the registry incorrectly. Before you modify it, back up the registry for restoration in case problems occur.
Start Registry Editor. To do this, use one of the following procedures, as appropriate for your version of Windows.
Windows 10, Windows 8.1, and Windows 8: Press Windows Key + R to open a Run dialog box. Type regedit.exe, and then press OK.
Windows 7: Click Start, type regedit.exe in the search box, and then press Enter.
In Registry Editor, locate and click the following subkeys, depending on the bitness of your Windows and Outlook installations.
For Windows 32-bit running Outlook 32-bit or Windows 64-bit running Outlook 64-bit: