How to include non-DocuWare users in workflow using email

We are looking for suggestions on how to best include non DocuWare users in workflows.

The client uses DocuWare on-premise with Import, SmartConnect, Workflow Manager and AutoIndex. A Cloud subscription may be added if justified and to introduce C2Mail and Forms.

A few rough ideas:
1-have the email user type Approve or Reject on the Subject line and forward to an email address. This will be received by Connect to Mail and used by AutoIndex to indicate the decision in the correct field and the workflow will continue accordingly.
2- have the user forward the email to either approve@email.xxx or reject@email.xxx with any comments. The address determines what the decision is and the workflow can take it from there. 
3-include links in the email text for Approve or Reject. What exactly to include is the question.
4-include a link to a DocuWare Form that simply allows to enter Approve or Reject and comments, but this would somehow need to be tied to the transaction being approved or rejected. Can parameters be passed to an online form in an URL so it prefills fields?

Any suggestions or additional ideas will be welcome.

Pedro 

Hi Pedro, 

Workflow tasks (almost) always require user interaction. The only exception to this is confirming workflow tasks via .NET/REST API. 
All your described ideas are not possible with default system behaviour, but you could implement any of them using custom programming via the API. 
Even Autoindex is not able to confirm a workflow task - it can only change index entries, which has no effect on already open tasks. 

Hope this helps. 

Greetings from Germany, 
Simon H. Hellmann
DocuWare System Consultant