offset error crazy

hey fellas im new to this forum and i got a problem. i've been filleting perpendicular elbows and offseting the fillet for the thickness of the material but now everytime i try to offset the fillet autocad spits back "cannot offset that object". it worked fine about 2 hours ago i think i might have changed something?

That's because you are trying to offset too far of a distance. An arc can only offset just so far towards its center. For instance, if you have an arc with a radius of 1.0, you can offset it .999 towards its center, but if you try to offset it 1.0 or more, you will get the message "cannot offset that object". So try offsetting a smaller amount. Something less than the radius of your arc.

but the parts i'm drawing need to be at a certain thickness so if the corners are too big the fillet wont offset but youre right instead of offseting the outter radius i'm doing the inner one and it works everytime. thanks.