My model is not being rendered correctly anymore

[mnarsi 0]

Hi everyone, I seem to be running into a strange problem. I am modeling some parts currently. I modeled the first one in, exported it and put it into Cura, it rendered perfectly. I exported it and printed it and it was perfect. No issues at all. Here is the part in blender and the final product:

 

I modeled the second part i need, and now it is being rendered all weird with in Cura. It looks perfectly fine in blender however. I took many different approaches to modeling it to try and solve the problem. It is still doing the same thing. Here is the new part I am having trouble with:

 

Here is what that part looks like in Cura: 

 

I started to think "Maybe it is the Cura software?" So I put back the original part that I modeled and printed at first that turned out perfect and now that one is being rendered weird as well. Here is what that original part looks like now in Cura:

I don't remember changing anything in Cura, but i may have by accident. I tried uninstalling and reinstalling, I tried removing and reading my printer. Still nothing. Does anyone have any ideas as to why this is happening? Thank you, 

[Curven 28]

It seem's like something in your STL that cura doesn't like... Try installing the mesh fixer plugin.

It will give you a message if there is a problem with your STL.

 

If you want you can also share your STL here so someone else can try to open it and see if the same thing occurs.