im on the phone right now with kingston for an "invalid upc code" on a rebate i submitted. i'm tired of companies doing this - when you submit a valid upc they tell you there was a problem, and usually that's that, you don't get your rebate.
word to the wise though, KEEP COPIES! otherwise, a "representative that accidentally typed in your upc number in wrong" (that's what they tell me may have happened) means you are screwed.
btw, kingston's representative just told me, "as a one time courtesy, i'm going to go ahead and validate your rebate, and you'll receive your check" etc... its such a shady operation.