Unable to access aperture settings or focus in manual mode

Hi, I changed the lens on my E410 to a zoom lens. When I went to shoot i could no longer set aperture or focus. I changed the lens back, but still can not access/choose fstop settings, the screen just has yellow dashes where it used to show the fstop number. The camera no longer focuses when i press the 'take' button down halfway. How can I restore full manual settings? I have been through the 'menu' and 'info' but can't find anything that fixes this.