Fixing crashes Windows Phone apps with crashinfo of dev dashboard

I have a simple wp8.1 app published in the store (universal app) but it crashed. So I downloaded the excel file containing crash info from https://dev.windowsphone.com/en-us/DownloadReport The crash(es) occur in the latest version of my app and the clients have 8.1 (because you cannot run universal apps otherwise)

Here is a small list of all problem functions and their exception type:

• mscoree!CoreCLRRunner::CoreCLRInstance::RunAssembly (APPLICATION_FAULT)
• windows_ni (STOWED_EXCEPTION_FINALIZER)
• twinapi_appcore!Windows::ApplicationModel::Core::CoreApplication::ForwardLocalError (WRONG_SYMBOLS_kernel32legacy.dll)
• windows_ui!Windows::UI::Core::CDispatcher::WaitAndProcessMessages (STOWED_EXCEPTION)
• bad_dump!stowed_exception_structure_invalid (STATUS_STOWED_EXCEPTION)

but I'd like to focus on the top one, because that occurred the most. This is the top Problem function mscoree!CoreCLRRunner::CoreCLRInstance::RunAssembly So here is the related stacktrace:

Frame Image Function Offset
0 ntdll.dll LdrAppxHandleIntegrityFailure 0x0000011a
1 ntdll.dll LdrpFindOrMapDll 0x000004f6
2 ntdll.dll LdrpLoadDll 0x00000248
3 ntdll.dll LdrLoadDll 0x00000050
4 kernelbase.dll LoadLibraryExW 0x00000084
5 CoreClr.dll CLRLoadLibraryExWorker 0x0000003c
6 CoreClr.dll CLRLoadLibraryEx 0x00000012
7 CoreClr.dll LoadedImageLayout::LoadedImageLayout 0x0000004e
8 CoreClr.dll PEImageLayout::Load 0x0000002e
9 CoreClr.dll PEImage::GetLayoutInternal 0x00000042
10 CoreClr.dll PEImage::GetLayout 0x000000d8
11 CoreClr.dll PEImage::HasNativeHeader 0x00000030
12 CoreClr.dll BINDER_SPACE::AssemblyBinder::GetAssembly 0x00000094
13 CoreClr.dll BINDER_SPACE::AssemblyBinder::BindByTpaList 0x0000024a
14 CoreClr.dll BINDER_SPACE::AssemblyBinder::BindLocked 0x00000040
15 CoreClr.dll BINDER_SPACE::AssemblyBinder::BindLockedOrService 0x00000030
16 CoreClr.dll BINDER_SPACE::AssemblyBinder::BindWhereRef 0x000000b4
17 CoreClr.dll BINDER_SPACE::AssemblyBinder::BindAssembly 0x00000150
18 CoreClr.dll CLRPrivBinderCoreCLR::Bind 0x00000060
19 CoreClr.dll AssemblySpec::Bind 0x000001fe
20 CoreClr.dll AppDomain::BindAssemblySpec 0x00000372
21 CoreClr.dll AssemblySpec::LoadDomainAssembly 0x000000f6
22 CoreClr.dll AssemblySpec::LoadAssembly 0x00000014
23 CoreClr.dll AssemblySpec::LoadAssembly 0x00000042
24 CoreClr.dll CorHost2::ExecuteAssembly 0x00000088
25 MSCOREE.DLL CoreCLRRunner::CoreCLRInstance::RunAssembly 0x00000080
26 MSCOREE.DLL _lambda_0f67c82022084a65857b171f2e9c0e8b_::operator 0x000001d0
27 MSCOREE.DLL _CorExeMain 0x0000000a
28 ntdll.dll RtlUserThreadStart 0x00000016

and I have no idea to fix all of these 5 crashes. My wp app is so small, it should be easy to have it bug/crash free.