Similar problem. DIR-655B, FW v. 2.00NA. Was installing a new NAS, couldn't get the UPnP to work. I read that it was likely due to a firmware issue--saw v.210 on the router's UI, installed it. That ended up killing the wifi (the signal was on/off on about a 3-second cycle). Some more reading led me to the download page, where I saw v. 2.11NA was the most current. I downloaded *that*, and installing it completely bricked the router. I can get to the "recovery mode" page (labeled "Firmware Upgrade System," v. 1.0.0.2, 2009/12/07, on my system). I've run through the process many, many times, trying both the 2.10 & 2.11 .bin files--I typically get nothing, but about 1 time in 10 it will give me the "wrong hardware ID" error.
Is it worth trying to downgrade to a previous version? (Was working fine on v. 2.00, less the UPnP with the NAS.) Where can I find the older f/w files? Thanks for any help!