Some edges are not shown in object wireframe mode? The wireframe on the right looks correct, but in object mode on the left, you can see that the upper and lower vertices are not connected, while the "box" to the right is fine.

I tried Fill and Merge Vertices, but both do not result in a correctly looking model. In wireframe mode, it looks great, but in object mode it does not.

I have uploaded my model here:

http://www.pasteall.org/blend/36955

Does anybody see what causes this weirdness?

Thank you for the help!

Here is another image: It shows that the 2nd "box" is not correct (it has greyish faces), while the 1st and 3rd are correct.
Blender doesn't show ALL edges by default in object mode.



To make all edges visible, go to Display Panel  in the Object Context
and check the "Draw all edges" box as in the picture.