ShelterLogic Canopy

In August of 07 I purchased and 10x10 ShelterLogic canopy through Northern Tool Co. I have used the canopy 9 times in the past year. The last time I used it I noted a corner strut had broken completely and one of the corner assemblies is badly cracked. Both Northern Tool and ShelterLogic have told me there is nothing they can/will do becuase the product has only a 1 year warranty. I have written to ShelterLogic asking that the frame be replaced as it is practically unusable and the damage has to be from defective construction or materials. I would certainly not purchase any product from ShelterLogic or Northern Tool again