strange landscape crash

[tegleg]

i made a landscape from a heightmap, 1024x1024, no sharp angles or anything.
when i drive a vehicle on 1 particular area, a gentle slope, when going up the slope it causes a crash every time.
heres the log

[0176.38] Log: === Critical error: ===
Fatal error!

Address = 0xebcba386 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\PhysXCore64.dll]
Address = 0xebed6c55 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\PhysXCore64.dll]
Address = 0xebe160e5 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\PhysXCore64.dll]
Address = 0x3ffaf9fc (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fb57b00 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fb57e87 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fb57e87 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fb57e87 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fb57e87 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fb57e87 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fb57e87 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fb57e87 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fb58fc9 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fa3ffc9 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x40acee6d (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x40ad1021 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fa5e0b6 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fa69ef4 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3fa6c22a (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x40597d31 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x406d7a0a (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x40a98ba0 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x40a99639 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x800c533e (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\wxmsw28u_core_vc_custom_64.dll]
Address = 0x8000413e (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\wxmsw28u_core_vc_custom_64.dll]
Address = 0x9fdc23   (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\wxmsw28u_vc_custom_64.dll]
Address = 0x800d6cc4 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\wxmsw28u_core_vc_custom_64.dll]
Address = 0x40a9de9b (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x40a9df5a (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x8cbd16d4 (filename not found) 
Address = 0x8cb81ee8 (filename not found) 
Address = 0xec1a255a (filename not found) [in C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll]
Address = 0x8cbd124e (filename not found) 
Address = 0x8b3f76   (filename not found) 
Address = 0x3f320000 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]
Address = 0x3f320000 (filename not found) [in C:\UDK\UDK-2013-07\Binaries\Win64\UDK.exe]

[DemoMan2]

Hello again Tegleg,
Here's some things you can try and see if it will make any difference in your level.

1.) Check your lightmass volume. If you happen to go BELOW the lower limit of a lightmass volume, I had the program crash before.
2.) Run a smoothing routine over the bad area of the map. Sometimes there's one vertex that's too low (i.e. a spike) that can cause you problems. It's worth a try.
3.) Check World zone info and make sure your not above the maximum or below the minimum values. That can cause you problems in a level.

Somehow, I suspect that you've already tried these but if not let me know if they make any difference for you.

[tegleg]

it is possible i was below lightmass volume, everything else should be ok.
ill give it a try thanks

[Farseer]

Perhaps you've encountered this same issue tegleg:

http://forums.epicgames.com/threads/...-2013-07-build

Would seem related, at least judging by the physx exploding in your callstack as well.