Has anyone heard of there being a limit on sequence or number of keys due to Mercedes chip/computer limitations? I recently purchased a '97 E320 with a single, switchblade key.The alarm and key functions worked fine until I ordered a standard key from the dealer. When I picked up the car after the dealer "programmed" the new key in, the new key worked but I later found the old key no longer started the car. Back to the dealer who said something like "OOPS! your switchblade key is from series "8", so it cannot ever be used again since it is at the top of the series." Two of the dealer's mechanics spent considerable time trying to re-program my switchblade key vs car including various door entry and ignition tricks from other cars but all for naught. Thanks for any help, Email replies, please just substitute "yahoo" for "nospam"