Help unroot emergency! HELP!!

[cooldude1]

so earlier today i officially decided that i was going to unroot my toshiba thrive because i never used any of the super user features and thought it was slowing my tablet down. so i followed the instructions to unroot but something went wrong. im both unable to flash a recovery image as well as a stock boot image. at the point in time that this post is written, i am unrooted but unable to update the system image. when i try to, i get the android guy with the triangle sign with the exclamation mark in it.