This bug has completely made UEFN useless at this point until it is fixed. I just spent the past 5 hours creating a new map in LEGO. Everything was going fine until I turned on Revision control. Within a few minutes of pushing my map into revision control, I was making coffee and came back to literally 1/2 of my entire map vanished…GONE!!
No big deal right, revision control, reverted back, got my map back. Great, went to play test it, my trigger I just placed wasn’t activating. Went into UEFN to look, trigger gone!!! Replaced it, 5 minutes later, trigger gone. Replaced it, renamed it, and attached it to another asset, GONE!!!
Serious question, how are any of you making maps? Are you just not using revision control?
EDIT: Not enabling revision control does not work. I just attempted to start building a new island and decided to not turn on revision control. I only have very few assets placed and already a large wall that I created just vanished.
I was having same problem after update 29.00 check for this, make sure your unreal editor For Fortnite is not running under an administrator. Fortnite has some Documentation depending on your system how to remove it. Check your Ransomware protection block history, see what folder are being block this can block revision control. Make sure SSD and NVidia driver is update after all that restart your computer. All of them were causing issues for me.
Possible Temporary Solution:
I have discovered after someone contacted me on Reddit that they found the issue was being caused by a sync problem with the UEFN Live Edit feature. It was suggested to disable the Live Edit in UEFN. I did this and at least for one solid afternoon of development, no assets vanished.
So thank you to that person and hopefully this will work for you as well until it is fixed. Note: this will not bring back any assets that vanished, only prevent them from disappearing again. If you need to bring back the assets, use revision control to restore a past snapshot. (Hopefully you had Revision Control turned on)