System.ArgumentException: An item with the same key has already been added.

Author: xordroid-86Created Jul 14, 2026Updated Jul 14, 2026

Note: if you do not provide all of the following information I will directly ignore and close this issue

  • Il2CppDumper version Il2CppDumper-win-v6.7.46
  • Target Unity version (optional) 2022.3.41f1
  • Describe the issue While dumping this pops up:
Initializing metadata...
System.ArgumentException: An item with the same key has already been added. Key: 69
   at System.Collections.Generic.Dictionary`2.TryInsert(TKey , TValue , InsertionBehavior )
   at System.Linq.Enumerable.ToDictionary[TSource,TKey](TSource[] , Func`2 , IEqualityComparer`1 )
   at System.Linq.Enumerable.ToDictionary[TSource,TKey](IEnumerable`1 , Func`2 , IEqualityComparer`1 )
   at Il2CppDumper.Metadata..ctor(Stream stream) in C:\projects\il2cppdumper\Il2CppDumper\Il2Cpp\Metadata.cs:line 102
   at Il2CppDumper.Program.Init(String il2cppPath, String metadataPath, Metadata& metadata, Il2Cpp& il2Cpp) in C:\projects\il2cppdumper\Il2CppDumper\Program.cs:line 123
   at Il2CppDumper.Program.Main(String[] args) in C:\projects\il2cppdumper\Il2CppDumper\Program.cs:line 97
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The game is for Android, it contains ELF64 libil2cpp.so