you can run just one instance of a workflow on an item.

so if you want the same workflow is executed on item change event as on new item event (ie. one that is already running), then it's simply not started hence can not execute terminate workflow action.

create one another workflow that will run on item change event and let terminate workflows from this extra workflow.

As the approval has not been made yet I wouldn't even necessarily see a new workflow start. Ones the approver gets to approve the element he will just see the latest version of the item to approve.

If you really need to interact, then you could have a second workflow that runs when the item is updated AND the approval workflow is running. That workflow could notify the approver that the item to approve had been modified or even restart the workflow. But personally - without knowing your scenario - I would just let the first workflow run.

Enrico,

Thanks for responding. Unfortunately, in  my situation, the approver is also selected (from a drop-down list in the form) by the author . So it is possible that the first time, the author selected Approver X, but before the approval task completed, the author could decide that it should really be Approver Y. So the author could make that change on the form and resubmit. Currently, without being able to terminate the first workflow instance,  Approver Y never gets the approval request notification (as the 2nd workflow instance does not start).

Marian,

Appreciate your reply. Your suggestion is a good one but it does not seem to resolve the situation I describe above for Enrico. For example:

First Submit (item created)--> Triggers Workflow 1 and sends out an approval request to Approver X

Second Submit before Workflow 1 completed (item was changed - say a form field was updated) --> this triggers Workflow 2 (which terminates Workflow 1 as you suggested) and sends out another request to Approver X

Third Submit before Workflow 2 completed (item was changed again - say this time the author changed his approver selection to Approver Y) -- this will not trigger any workflow instance and Approver Y will never get an approval request.

After giving Marian's idea some thought, I think the following might work:

Create 2 workflows (Workflow X and Workflow Y).

Workflow X runs on Item Create as wells as Item Change

Workflow Y runs only when Approver field is changed (this workflow terminates Workflow X and after that performs the same actions as Workflow X)

If the author changes the item (but not the approver field), the original approver will not receive any new notification, but will be able to review the changed item.

No need to implement the same logic twice.

My idea was workflow X starts on item create, workflow  Y starts on item change and first terminates running workflow then starts workflow X. Make sure workflow Y doesn't wait until workflow X ends.