V715w setup to print with ipad

We are using  Printagent Pro to print with with our ipad using a pc as a print server (not sure of the technical terms) on our wireless network.  When trying to set it up to use with an iphone it wants the printer username and password.  I have no idea anymore what to put in.  When I go into the printer info it shows a password was never set up for the printer and I have no idea what the username would be.  I have tried using admin for both and that doesn't work.  Does anyone have any idea what I could try?  It seems I have tried everything including the router password etc.  Any help would be greatly appreciated.  If no one knows the answer do you know what number I could call at Dell to try to figure this out. Thanks.