I was racking my brain on this one for some time so I thought I would share what I did to get my iEdge card to work in a firmware 1.4.1U locked DSi. Maybe this is already common knowledge, but I spent a good three hours figuring this out. Hopefully this will save someone time. Background DSi was accidentally upgraded to firmware 1.4.1U. I was already running an iEdge card under firmware 1.4U with no problems before this happened. After the accidental upgrade the DSi locked the iEdge card and displayed the dreaded "An error has occured..." message. Problem No matter how many times I tried to upgrade the iEdge card, using the ROM and bootstrap from the edge website, or bitonio6's total bootstrap package, nothing was working. It always resulted in the same "an error has occurred... message". Apparently, if you upgrade your firmware and try to use the same card, the DSi will lock that card out, or block it from working. It can not be upgraded in the same DSi. Solution Luckily I have a second DSi that was still running the 1.4U firmware. Using the steps posted here a dozen times I upgraded the "blocked" card using the V3 bootstrap and OS 2.0 but I used the second DSi running the 1.4U firmware instead. I then put it into the original DSi that had blocked that card and it worked! So the key is to use a second DSi running an older firmware. Credit There was one sentence in one post by bitonio6 that led me down the right path. Thank you!