Sending automatic customer acknowledgement emails

Hi,

I have set up an automatic customer acknowledgement email workflow, one that triggers an email to the customer when they submit an enquiry on our website (using Web2CRM application).

The workflow works fine (customer recieves acknowledgement email) when the email comes from me, but when I change the 'From' feild to another user, the customer does not recieve the acknowledgement email.

I would like to know how I can change this, so these emails are sent from a generic user or no reply user?

Any tips would be greatly appreciated.

Cheers

Aidan