Crash when projectile spawns

[Rymaca]

Since the implementation of the content of this lesson I get this crash whenever a projectile is spawned.
The line that is referenced in the Projectile.cpp is
Mesh->OnComponentHit.AddDynamic(this, &AProjectile::OnHit);
And the line thats referenced in the BasePawn.cpp is
auto Projectile = GetWorld()->SpawnActor<AProjectile>(ProjectileClass, Location, Rotation);

Both code lines where there before and working just fine. I don’t know exactly what the crash report is telling me, so any help would be appreciated!

Assertion failed: DelegateOwner->IsValidLowLevelFast(false) [File:H:\Unreal Engine\UE_5.0\Engine\Source\Runtime\CoreUObject\Public\UObject\SparseDelegate.h] [Line: 196]

UnrealEditor_ToonTanks!AProjectile::BeginPlay() [H:\Unreal Projects\ToonTanksProject\ToonTanks\Source\ToonTanks\Projectile.cpp:31]
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UnrealEditor_ToonTanks!ABasePawn::Fire() [H:\Unreal Projects\ToonTanksProject\ToonTanks\Source\ToonTanks\BasePawn.cpp:49]
UnrealEditor_ToonTanks!TBaseUObjectMethodDelegateInstance<0,ATank,void __cdecl(void),FDefaultDelegateUserPolicy>::Execute() [H:\Unreal Engine\UE_5.0\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:594]
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kernel32
ntdll

[DanM]

Could you try a rebuild by closing Unreal and then deleting the Binaries and Intermediate folders. Then re-open the project and rebuilding when prompted.

[Rymaca]

Unfortunately, this did not work and the problem still exists.

[DanM]

Is it the same error

Assertion failed: DelegateOwner->IsValidLowLevelFast(false)

[Rymaca]

Yes. The crash report is identical

[DanM]

In that case would you mind sending me your project using the following link?

https://gdev.tv/projectupload

Please use File > Zip Project within Unreal as this will ensure only required files are zipped up and things like the Binaries are excluded.

[Rymaca]

I found the solution in this thread: Assertion failed: DelegateOwner->IsValidLowLevelFast(false)

Deleting the blueprint and recreating it from its C++ class solved the problem. Thanks for your support though!
Are these kind of bugs common? Or was I just unlucky? I am asking myselfe why the experience in unreal with an IDE is so bumby in comparison to what I have experienced with working with blueprints only.

[DanM]

I’ve rarely encountered this issue but I feel like I’m a unicorn based on the amount of people I see running into these kinds of issues.