4.8preview crash

no matter what i do, the engine will crash.
click play:![alt text][1]
click compile:

here is the log:

[2015.06.07-02.32.43:326][996]LogWindows: === Critical error: ===
Fatal error!

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x00000030

UE4Editor-CoreUObject.dll!UObjectProperty::GetObjectPropertyValue() {0x000007feed15fa10} + 0 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-CoreUObject.dll!UObjectProperty::SerializeItem() {0x000007feed2b6a94} + 21 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-CoreUObject.dll!UStruct::SerializeBin() {0x000007feed19a143} + 275 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-CoreUObject.dll!UStructProperty::StaticSerializeItem() {0x000007feed2ba61e} + 0 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-CoreUObject.dll!UStructProperty::SerializeItem() {0x000007feed2b6bca} + 0 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-CoreUObject.dll!UArrayProperty::SerializeItem() {0x000007feed2b51e7} + 39 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-CoreUObject.dll!UStruct::SerializeBin() {0x000007feed19a143} + 275 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-Engine.dll!UBlueprintGeneratedClass::AddReferencedObjectsInUbergraphFrame() {0x000007fee9b12f7b} + 24 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-CoreUObject.dll!FArchiveRealtimeGC::ProcessObjectArray() {0x000007feed22516c} + 0 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-CoreUObject.dll!TGraphTask::ExecuteTask() {0x000007feed1f8bd4} + 0 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-Core.dll!FTaskThread::ProcessTasks() {0x000007feec79605e} + 0 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-Core.dll!FTaskThread::ProcessTasksUntilQuit() {0x000007feec79628d} + 0 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-Core.dll!FTaskThread::Run() {0x000007feec7a528b} + 0 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\sou
UE4Editor-Core.dll!FRunnableThreadWin::Run() {0x000007feeca561c8} + 0 bytes [d:\buil

Hi skatebill,

Does this happen with the same project, or with any project? Can you create a new project and get the same result?

Hi skatebill,

We have not heard back from you in a few days, so we are marking this post as Resolved for tracking purposes. If you are still experiencing the issue you reported, please respond to this message with additional information and we will offer further assistance.

Thank you.