engine light - egr insufficient flow

Hello,

Has anyone experienced this problem: the engine check light pops on and stays on. The diagnostic device at a local auto parts store says "egr insufficient flow"" when it was plugged into my ECU. What do you think this means and what should I do about it? I did a search on this forum, but couldn't turn up anything. Thanks.

what year? possibly DPFE

Same thing happen to mine,it also was the DPFE,got one at NAPA