This question will be very similar to this one, but I'm stuck and don't know what to do:

Token contract source code not verified

Anyways, my friend sent me 2 pieces of code, the actual contract code, which can be found here:


And the interface:


Now I'm a coder and I understand that pasting just the first part of the code obviously wont work, so I deleted the import part and pasted in the interface. Then I ran the solidity-flattener over the code, and this is the output:


However, the code isnt being verified on https://etherscan.io/verifyContract2 I get the following error:


What should I do, what am I doing wrong? The contract address is 0x3C403c5371113a7d3f91d4b9C9A88333Ca567e74, the compiler 0.4.21+commit.dfe3193c and contract name Victory.

Thank you for your help.

  • 1
    2) Constructor Arguments ABI-encoded (For contracts that accept constructor parameters): Did you supply the ABI code for the constructor arguments?
    – vhie
    Oct 26, 2018 at 0:48
  • I did, still have the same problem. If I compare expected result and my generated bytecode, my bytecode is substantially shorter. Oct 26, 2018 at 8:34
  • Have you tried Optimization = No?
    – vhie
    Oct 26, 2018 at 9:03
  • Yes, but the optimization must be Yes, because that's what my friend did when he created the contract. Oct 26, 2018 at 11:12
  • How were the contracts deployed? Did you try different versions of the compiler? You may also try setting optimization runs to 0.
    – Ismael
    Oct 26, 2018 at 19:36

1 Answer 1


I successfully verified your contract in Etherscan and Blockscout: https://etherscan.io/address/0x3c403c5371113a7d3f91d4b9c9a88333ca567e74#code https://blockscout.com/eth/mainnet/address/0x3c403c5371113a7d3f91d4b9c9a88333ca567e74/contracts

I think the problem was with the wrong constructor arguments provided. But since Etherscan made the possibility to automatically auto-fill constructor arguments, verification process became easier.

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