In the Process Flow Advanced properties section there is a Recoverable Process Flow checkbox.

If we have this Recovery option checked (True)

- Then during process execution if the flow is interrupted (i.e., machine is restarting) then it will automatically recover and execute the flow from the last executed activity.

If we have this Recovery option un-checked (False)

And we don't put the Checkpoints explicitly in the flow

- Then it won't recover on system restart

If we have set the Recovery to FALSE and we put the checkpoints explicitly in the flow

- On restart the flow would start from the last explicit checkpoint