Also Virtual Memory is fairly important, check in your advanced PC settings and make sure you can get 32Gb minimum, 64Gb recommended. Windows will give you a small amount by default, but it needs more
But thats not going to solve the issue.
If your map is not the issue, some things can get stuck in the HLOD layer, like references to deleted custom stuff, remove HLODs from the build menu does not remove these.
I’m also suspecting using texture data assets on props, sometimes can bug it out.
You can try replacing it, you can simply make a new HLOD layer, drop it into the World Settings in both the default HLOD slots ( or only the 1 if your using the older World Streaming).
Deleting the existing one gives a few reference issues, that you do not want to save, otherwise follow the steps below.
This is how I replace HLOD Layer (pasted from a text file)
- Close Fortnite Edit/Play Mode if its running
- Check-in Changes and make a snapshot with URC for backup
- Make a new HLOD Layer in Content Browser - Right Click>World>HLOD Layer
- Delete existing HLOD Layer - Replace References to the new one - DON’T Save When it asks, otherwise it will keep the bad references in the HLOD
- Double Click on Level Thumbnail in Content Browser to reload map, can save if prompted
- Do a Build Landscape - ignore Yellow Warnings - use drop down filter to deselect them - deal with any Red Errors
- Double Click your Level Thumbnail again, Save.
- Build HLODs
- Try to launch session