Structure: "Cannot parse value" - Corrupts entire project

So I need to change something in a struct that is used in another struct. I know UE4 has issues with this, even years after they said they would fix it as per this thread:

Was wondering if anyone knew of any workaround? If I try to just add a variable to my struct it literally just breaks and corrupts the entire project and the only way to fix it is to restore a backup version. And once the variable is made, the struct can never be unbroken. Deleting the variable does nothing, the struct breaks and it stays broken.

The error message I can see in the struct that prevents it from compiling says "Cannot parse value. Property: Slot String: “NewEnumerator13”. But it’s not even an enumerator I am adding, it’s a simple integer.

I suppose the only way to perform the desired change is by remaking the entire struct and going through my functions one by one and fixing them up.

Updating to this as per the old thread I deleted to remake it into a bug report:

The entire project is literally broken. I must’ve crashed at least 10 times the last 20 minutes. I attempted to make a new struct with the additional variables I needed but it was already too late at this point, it got corrupted by my attempting to edit the struct in the first place. I reopen the project only to find a whole mess of variables and widget elements deleted.

This is pretty serious. Anything I do can cause the project to crash now, it is literally completely destroyed. Luckily I had the good sense to do a full backup before editing the struct, otherwise I would have lost months of work.


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This has happened to me as well.
The problem seemed to be casued by removing the default value of an enumerator present in the structure I’ve made.

The solution was simply change the default Enum value in the structure then change it back to the desired one and re-save the structure.

Seems like Structures does not auto-correct/fix the default Enumerator value when changed in the enumerator. So we need to go to each structure and set it manually.

See my example below. I had to select TRIGGER TYPE to be “Generic” Cause I had one named “None” which I removed and the structure had that one as default, not the “Generic” one. So I just set it back manually. This fixed it.

Hope this helps. Happy Devving!

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This still can happen inside ue5.1
1: Pack project…
2: in output log set filter for messages off… ( So you see only error and warnings).

The structure will be shown as error message that it can not compile…
3: Open you structure… there will be a stop sign on in left top corner…
hover you mouse over it … it will say what struct item is giving the error…
4: Replace the default values … …
5: Save structure…

now your project is able to compile again… thx @PhoeniX-Storms … :slight_smile: it was indeed the structure default values … that can even break in the new version of the engine

I faced this problem in 5.1.1 Found your post. And then I found a solution. After changing the structure, if it is used in another structure, then it must be removed from this structure (after copying the exact name of the structure) and re-added. If this structure is also used in another structure, then repeat the operation :slight_smile:
Perhaps you have found another solution in 4 years?