Unable extrude from a dxf file

[MetalRipper_]

I'm trying to extrude without the profile in the middle, but I am not able to do it. Kindly help.

Thanks

[jeff_strater · Accepted solution]

use divide-and-conquer to find the problem:

In the end, there is a small gap here - fix it with a coincident constraint:

repaired design is attached, FYI 

[MetalRipper_]

Thanks for tip "Divide and Conquer". Worked like charm. Thank you Jeff.