1) If you are are using a 2D sketch, go to 2) and 3) below.
If you are using a 3D sketch and your intent is for 2D cutting, first check in SW that the points (including handle points) in your curve are all on the same plane. Enter the sketch and select the curve in question to display this info, then select each point. One coordinate should stay the same for all points. If some points differ in this coordinate then set that coordinate to match the others and export your file again.
(If your sketch uses a plane that that is not parallel to front, top or right planes, then you will have to rotate your sketch/entity to be parallel or on the front, top or right planes.)
If that did not help, go to 2) and 3) below.
2) Try adding a few spline points on your curve in SW to see if that makes a difference.
3) If that does not work, then try splitting your curve in a few places in SW and see what happens.
It was't a sketch it was a SW drawing file saved as a DWG.
I never found out the problem, I ended up redrawing the bad curve in another program within the exported DWG file.
I hope it doesn't happen again as some curve are not that easy to redraw outside of SW and have them correspond to the original model. Luckily this one was.
Was the curve originally created in SolidWorks or imported?
The curve may have been nonplanar, and then was projected to 2D, which could cause a loop.
The handles on your curve may have been moved in such a way as to cause the curve to loop.
If the curve has a lot of nodes or closely spaced nodes, it is often harder to detect these problems.
The part was modeled in SW 2009 and a 2D drawing was created from the part. The drawing was then saved as a DWG file and opened in AutoCAD.
There was no imported work used all was created inside SW.
There were no splines all curves were dimensioned.
The edges used were on the same plane I THINK, or they should have been at least – that may have something to do with the looping.
what cam package are you running
Do you have the sketchs of some of the features visible in the SW drawing before you save as DWG/DXF?