The pictures almost says it all. I must add that I have tried to export and reimport the landscape, but the issue persists.
This is my main project, please I need help. I’m a lone developer and this Island has taken at least a week to model that I would love to not do again 
Why is the landscape cut like this???
Hi ImperiumPandemonium,
Are you using a tiled landscape or an imported heightmap or is this one that was made purely in editor? Have you tried running the smoothing tool over the seam with 0.0 tool strength?
Hi !
I have tried smoothing and nothing. The landscape is made purely in the editor.
I found a wierd solution. When painting the grass layer it corrects itself, but only grass solves it. In the image you can see how the grass layer fixed the crack.
What Engine Scalability Settings are you currently using?
I am using Epic scalability, I have all the highest settings.
My PC specs are : ASUS Rampage V Extreme with Intel i7 5960x, Asus GeForce GTX 980 Strix and 32GB RAM. I haven’t had this issue before.
Does this occur on a blank project with no additional content? Your PC Specs are well above what is needed so I’m fairly certain that is not the problem. We’ve had errors in the past with lower scalability settings but that certianly won’t apply in this instance.
No it doesn’t occur on a blank project.
Let me reiterate once more, I have not had this problem occur on this exact landscape with its material I’ve created.
After one autosave it just became like that and I can’t revert it back now. The autosaves have already gone one round since it happened. That would mean from autosave 1-10 atleast one full time.
What was the last action you took before this happened? What specific tools were you using just before the autosave kicked in and the seam seemed to detach?
I was playing with the heightmaps of my textures trying to create tessalation on my material. I’ll revert those changes to debug/test the material to see if that is what’s causing the problem. If i’m lucky the seams will reattachs by this small change. But then I won’t be able to use world displacement either though 
Hi ImperiumPandemonium,
Are you still experiencing this error or did removing tessellation help?
Hi ImperiumPandemonium,
We have not heard from you in several days. I am marking this thread as answered for tracking purposes. If you are still experiencing this error, please comment with the requested information.
Hi !
I have been quite busy at late, but yes the culprit was the tessellation. So how do I use heightmaps if my landscape gets a bunch of cracks because of it? I tried the flat tess and PN triangles, both with crack-free box checked and then unchecked. So cracks either way.
I am using 4.7.6 btw 
Cheers
Can you post a screenshot of the wireframe from your landscape components, specifically over one of the cracks that you are seeing?
I forgot about this post. Saw it just now and I thought I had answered, but I had not.
The issue at hand turned out to be quite simple, the cracks was just caused by too low resolution on my landscape, so tessellation didn’t work.
I have a VERY large landscape so I can’t have a matching resolution without killing my computer in the process. So my “tessellation” will really be instanced meshes that are texture blended with the ground. As to fake a tessellation.
