WD sent a non-HCL replacement for my dead WD20EARS

I think what is at issue here is the OP did have a compatible disk and through no fault of their own was given a larger, incompatible disk as a replacement through the WDC RMA process. He/she didn't go out and select and purchase the 3 TB drive and didn't choose the 3 TB as the replacement for the dead 2 TB. Under most circumstances a larger disk would be a positive however in this case the OP will now need to spend money to purchase another disk because the replacement is not compatible with his RN. Different than it simply not being on the HCL this 3TB disk will in fact be recognized as ~ .7 TB rather than 3 TB or 2 TB making it an unusable disk for the OP.