Crash when opening UMG widgets in 4.10

I upgraded a project from UE4.8 to UE4.10. Now, when I open UMG widget Blueprints, the Editor crashes. I’ve had this crash happen on both the OS X and Windows binary versions. The CrashContext-runtime.xml file (generated during a crash on Windows 10), lists the error as:

Assertion failed: IsValid() [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.10\Engine\Source\Runtime\Core\Public\Templates\SharedPointer.h] [Line: 739]

I was able to replicate the error in a blank project by migrating the problem file (and all linked files) to the blank project.

I’ve pasted the full contents of the CrashContext-runtime.xml file below (I couldn’t attach the file) (for privacy I redacted the MachineId and EpicAccountId:

<?xml version="1.0" encoding="UTF-8"?>
<FGenericCrashContext>
<RuntimeProperties>
<Version>1</Version>
<ProcessId>3620</ProcessId>
<IsInternalBuild>0</IsInternalBuild>
<IsPerforceBuild>0</IsPerforceBuild>
<IsSourceDistribution>0</IsSourceDistribution>
<GameName>TestProject</GameName>
<ExecutableName>UE4Editor</ExecutableName>
<BuildConfiguration>Development</BuildConfiguration>
<PlatformName>Windows</PlatformName>
<PlatformNameIni>Windows</PlatformNameIni>
<EngineMode>Editor</EngineMode>
<EngineVersion>4.10.0-2758231+++depot+UE4-Releases+4.10</EngineVersion>
<CommandLine></CommandLine>
<LanguageLCID>1033</LanguageLCID>
<DefaultLocale>en_US</DefaultLocale>
<IsUE4Release>1</IsUE4Release>
<UserName></UserName>
<BaseDir>C:/Program Files/Epic Games/4.10/Engine/Binaries/Win64/</BaseDir>
<RootDir>C:/Program Files/Epic Games/4.10/</RootDir>
<MachineId>redacted</MachineId>
<EpicAccountId>redacted</EpicAccountId>
<CallStack></CallStack>
<SourceContext></SourceContext>
<UserDescription></UserDescription>
<ErrorMessage>Assertion failed: IsValid() [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.10\Engine\Source\Runtime\Core\Public\Templates\SharedPointer.h] [Line: 739] 

</ErrorMessage>
<MiscNumberOfCores>4</MiscNumberOfCores>
<MiscNumberOfCoresIncludingHyperthreads>8</MiscNumberOfCoresIncludingHyperthreads>
<MiscIs64bitOperatingSystem>1</MiscIs64bitOperatingSystem>
<MiscCPUVendor>GenuineIntel</MiscCPUVendor>
<MiscCPUBrand>      Intel(R) Core(TM) i7-3720QM CPU @ 2.60GHz</MiscCPUBrand>
<MiscPrimaryGPUBrand>NVIDIA GeForce GT 650M</MiscPrimaryGPUBrand>
<MiscOSVersionMajor>Windows 10</MiscOSVersionMajor>
<MiscOSVersionMinor></MiscOSVersionMinor>
<CrashDumpMode>0</CrashDumpMode>
<MemoryStatsTotalPhysical>17082032128</MemoryStatsTotalPhysical>
<MemoryStatsTotalVirtual>140737488224256</MemoryStatsTotalVirtual>
<MemoryStatsPageSize>4096</MemoryStatsPageSize>
<MemoryStatsTotalPhysicalGB>16</MemoryStatsTotalPhysicalGB>
<MemoryStatsAvailablePhysical>12283076608</MemoryStatsAvailablePhysical>
<MemoryStatsAvailableVirtual>140735379156992</MemoryStatsAvailableVirtual>
<MemoryStatsUsedPhysical>875036672</MemoryStatsUsedPhysical>
<MemoryStatsPeakUsedPhysical>875036672</MemoryStatsPeakUsedPhysical>
<MemoryStatsUsedVirtual>1391919104</MemoryStatsUsedVirtual>
<MemoryStatsPeakUsedVirtual>1391919104</MemoryStatsPeakUsedVirtual>
<MemoryStatsbIsOOM>0</MemoryStatsbIsOOM>
<MemoryStatsOOMAllocationSize>0</MemoryStatsOOMAllocationSize>
<MemoryStatsOOMAllocationAlignment>0</MemoryStatsOOMAllocationAlignment>
</RuntimeProperties>
<PlatformProperties>
<PlatformIsRunningWindows>1</PlatformIsRunningWindows>
</PlatformProperties>
</FGenericCrashContext>

Here is a workaround for the issue:

  1. Create a blank Blueprint project in UE 4.9
  2. In UE 4.10, Migrate your UMG asset to the blank UE4.9 project (make sure to migrate all referenced files)
  3. Make changes to UMG file in UE4.9 project
  4. Copy the UMG .uasset file (and any modified referenced files) from the UE4.9 project’s Content folder into your UE4.10 project’s Content folder, overwriting the file in the UE4.10 project

This allowed me to fix an issue with the size of an image in the UMG widget. And, when I play the game in PIE in UE4.10, the fix is retained.

maybe it can help : link text

Thanks for the link. I’ll give it a go.

The workaround in the following AnswerHub question solved the issue: [Assertion failed: IsValid() File:D:\BuildFarm - UI - Epic Developer Community Forums][1]

I was able to use this workaround to access the UMG Blueprint in both the Windows and OS X binary versions of 4.10.0.

Here’s the answer from that post:

We were able to reproduce this crash
in a clean project. We have written up
a report (UE-23217) and it has been
submitted to the developers for
further consideration. I will provide
updates with any pertinent information
as it becomes available. During
testing we found that the issue was
caused by closing the animation and
timeline windows. Thank you for your
time and information.

Workaround:

Window > Reset Layout will allow you
to open the blueprint again.

66397-resetlayouthelp.png

Possibly related

Can confirm that this solution works as I had this same issue.