The link I posted was the only one I needed to get my e250 up and going again. I had to do the steps several times (four I think) but eventually it worked. Dropping the the mi4 file and the sansa.fmt into the 16 mb recovery drive eventually worked.
There are other threads about the database refreshing problem
but I have no personal knowledge of how to do that. There is also a thread a thread in the Rockbox Twiki on how to unbrick a Sansa
V1 and how to use manufacturing mode in Linux.
Hope one of these works for you. Good Luck.