26 votes
Accepted

Error when trying to verify contract

I got this error too and this worked: Delete artifacts and cache folders run npx hardhat compile then verify
Jack's user avatar
  • 276
16 votes
Accepted

Convert contract arguments from JSON to ABI-encoded format

The page "Verify Contract" ask for "Constructor Arguments ABI-encoded". In your case the constructor has no parameters, so you can leave such field empty. In the general case when your constrctor ...
Ismael's user avatar
  • 30.6k
12 votes
Accepted

Etherscan: How can I verify a contract with multiple imports deployed with Truffle?

Currently etherscan does not support verification of multifile contracts. But there is discussion on etherscan's reddit about this issue. Concatenating files into one worked some time ago, but since ...
max taldykin's user avatar
  • 2,966
9 votes

How do you verify a contract on etherscan that is deployed by another contract?

It is not possible as on 24th March 2018. Etherscan is unable to locate contract code on the address of subcontract. Here is the transaction which deploys two contracts. But for the second contract, ...
Ayushya's user avatar
  • 1,698
8 votes

Error when trying to verify contract

You will need to delete the files and recompile: run npx hardhat clean run npx hardhat compile try verify again. npx hardhat clean deletes cache and artifacts :)
brayve pancake's user avatar
7 votes

How do you verify a contract on etherscan that is deployed by another contract?

I have deployed a contract from another contract: https://etherscan.io/tx/0x8fd885ce7ad7b6a591d9614d41cbb1d97aa7d2e290f6aa52531ce3d4c799a5ff which deployed: https://etherscan.io/address/...
rstormsf's user avatar
  • 4,337
6 votes
Accepted

How to verify a contract having constructor arguments?

You need to correctly ABI-encode constructor arguments. You can easily do this with online tool https://abi.hashex.org. Just paste in abi to automatically parse constructor parameter types or add them ...
Gleb Zykov's user avatar
6 votes
Accepted

Possible to change Etherscan verified source after initially verified?

I don't think so. If you could, then anyone could come along, copy the source code, and reverify it with completely different comments, which opens up for all types of attacks, including phishing. You ...
natewelch_'s user avatar
6 votes
Accepted

Verifying a Token Contract with Interface

Guys I really hate my life. It took me over 10 hours to find the solution to this problem. I compiled the contract with various different methods. Deployment worked with each of the but the contract ...
cqx's user avatar
  • 3,462
6 votes
Accepted

Besides Etherscan, Are There Other Places to Verify/Publish Contract Code?

Etherscan is the most cut-and-dry, but there are at least a couple of other resources available: SmartContract.Codes - a p2p search engine for smart contract source code. ethPM - a decentralized ...
iamdefinitelyahuman's user avatar
5 votes
Accepted

How to verify a paper wallet is working without compromising the private key?

There are a few different reasons for verifying your key. To make sure you actually saved the private key and address correctly. e.g. You saved a private key but recorded the address 0x122... ...
tayvano's user avatar
  • 16k
5 votes

How do you verify a contract on etherscan that is deployed by another contract?

If you're a Hardhat user, you can use the hardhat-etherscan plugin: $ yarn hardhat --network NETWORK_NAME verify CONTRACT_ADDRESS --param1 --param2 It works even with contracts deployed by other ...
Paul Razvan Berg's user avatar
5 votes

Can ZKSnarks be implemented on the Ethereum ecosystem?

Disclaimer : I am not a cryptographer nor a mathematician nor a low level software engineer. Please correct me if any information provided below is incorrect. Very short answer: Yes Short answer: ...
PhABC's user avatar
  • 522
5 votes
Accepted

How to verify smart contracts on different solidity versions

The article is fairly old. I'd suggest taking a look at the current docs on Contract Medatata. They contain these notes: The CBOR mapping can also contain other keys, so it is better to fully decode ...
cameel's user avatar
  • 2,211
4 votes

Convert contract arguments from JSON to ABI-encoded format

In case you want to use a simple online tool to encode parameters you may use https://abi.hashex.org You can enter abi to automatically parse parameter types or just enter them manually. In Function ...
Gleb Zykov's user avatar
4 votes
Accepted

Unable to verify Solidity contract code on etherscan.io

I was able to verify my contract with optimization turned on, when compiling from remix: https://ethereum.github.io/browser-solidity/ For some reason, it produces a different bytecode from Parity, ...
Jesbus's user avatar
  • 10.5k
4 votes
Accepted

Is there a way to verify the identity of the sender of the transaction in ethereum?

It depends on how strongly you want to verify the identity: If you want a person, who you already knew, to prove that they sent the transaction, it's easy: They can just attach a piece of data to the ...
Jesbus's user avatar
  • 10.5k
4 votes

Cannot verify contract with multiple arguments at etherscan.io

You need to correctly ABI-encode your constructor parameters. You can easily do this with online tool https://abi.hashex.org. Just paste in your abi to auto-parse constructor parameters or manually ...
Gleb Zykov's user avatar
4 votes

Etherscan: How can I verify a contract with multiple imports deployed with Truffle?

I built a CLI that may help you, called multisol. You can install it via Homebrew if you're on Mac, or download one of the executables I provide if you're on Windows or Linux: $ brew tap paulrberg/...
Paul Razvan Berg's user avatar
4 votes
Accepted

Why doesn't my verification of a signed message signature work in PHP?

After much head-banging (against the wall) and isolating the issue to the hashing of the resultant public key, (nicely summarized in my other question, here: Why doesn't my private key's ...
EvilJordan's user avatar
3 votes

Can't verify contract on etherscan.io

I was able to successfully verify the contract code you linked in a new deployment. Are you sure the parameters and source code you used were identical to those you used in the verification tool? ...
Travis Jacobs's user avatar
3 votes

Having trouble verifying a contract on etherscan.io

In case you want to use a simple online tool to encode parameters you could use https://abi.hashex.org You insert the abi code to automatically parse parameters types or just enter them manually. In ...
Dmitry Mishunin's user avatar
3 votes

I can't verify my contract on the Rinkeby etherscan site

The compiler was timing out, and documentation online suggested that truffle optimizes the compilation -- nevertheless, I selected "no" for the optimized option, and didn't enter in the library ...
nickjm's user avatar
  • 865
3 votes
Accepted

Cannot verify Contract - bytecode has small difference

Let's see what happens here. In solidity v0.5.11, the end of the bytecode includes the following : 0xa2 0x65 627a7a7231 => "bzzr1" in hex 0x58 0x20 <32 bytes swarm hash> 0x64 ...
clement's user avatar
  • 4,302
3 votes
Accepted

How to verify a signed message and that it hasn't been reused/tampered with?

1st sign the message. The message has to have to signer address in it. We will parse this message and get the signer address and compare it to the one we get from decoding the signed message. If they ...
YulePale's user avatar
  • 1,843
3 votes

Automatic verification of Smart Contracts deployed from another Smart Contract

Contract verification is an off-chain process. For etherscan for instance, the code is stored by Etherscan and they just verify that the bytecode matches. You can create scripts off-chain however to ...
thefett's user avatar
  • 3,873
2 votes

Having trouble verifying a contract on etherscan.io

I was able to verify the contract on Etherscan by checking the "Input Data" of the transaction that created the contract. It includes the contract bytecode and the constructor argument bytecode right ...
milkywaymasta's user avatar
2 votes

Having trouble verifying a contract on etherscan.io

Sorted. Had pasted contracts in wrong order Removed import references Pasted constructor argument bytecode from end of deployed TX
o0ragman0o's user avatar
  • 4,320
2 votes

How to verify Mist's standard multisig wallet using Etherscan tool?

The contract you're looking at is a stub. If you look at the contract's code and select Switch to Opcodes View, you can see it references another contract at 0x273930d21e01ee25e4c219b63259d214872220a2 ...
Dennis Estenson's user avatar
2 votes
Accepted

Is it possible to verify a given `block hash` is valid in a contract?

Q1: I don't see an obvious way to do that without getting into a gas-expensive loopy process that won't scale. A web3 client would be better suited to searching for it in my opinion. Q2: I would ...
Rob Hitchens's user avatar
  • 55.2k

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