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Has the Kodak printer/fax machine worked, with regard to faxing, OK prior to this?
If it isn't a new setup for faxing, then I presume you have gotten the phone line connected correctly to the Kodak device's correct jack. (That would be the 'line' jack not the 'phone' jack, which is for 'phone extentions.')
Can you receive faxes? if so, did you recently change your phone line service provider? More urgently: Did you recently change to a digital phone service? if so, that switch in service type, could explain difficulty with faxing. Digital phone line service very often does not support the high frequencies needed for fax communication, and faxing cannot be done over such lines. At very least, before concluding that is the problem, if possible the faxing device should be set to a slower Tx/Rx speed, &/or set to disable 'ECM' mode in the device's Fax Settings.
But tell me about other aspects of the problem... can your receive faxes OK, what is the line service type, did this work sending faxes before this, and so forth. And I will advise you further.