I tried this (what rfisher71 did) but it is still showing the accrued market discount from my 1099-B increasing my capital gain AND the accrued market discount, after entering the number in error mode as you did, increases my interest expense too. Was this not an issue for you?
Edit - I think making the adjustment directly to the capital gain loss sheet as rjs's post showed is a way to do this, but I hate to have to go out of "step-by-step" mode to do this, it makes me scared of where else I could be double paying in step by step and not realizing it...
