I had been connecting to the ropsten testnet for the past couple months in geth with no issues, and able to quickly sync to the latest block. Now when I connect to ropsten as follows (as I've always done):

geth --testnet --syncmode "fast" --rpc --rpcapi db,eth,net,web3,personal --cache=1024 --rpcport 8545 --rpcaddr --rpccorsdomain "*" --bootnodes "enode://20c9ad97c081d63397d7b685a412227a40e23c8bdc6688c6f37e97cfbc22d2b4d1db1510d8f61e6a8866ad7f0e17c02b14182d37ea7c3c8b9c2683aeb6b733a1@,enode://6ce05930c72abc632c58e2e4324f7c7ea478cec0ed4fa2528982cf34483094e9cbc9216e7aa349691242576d552a2a56aaeae426c5303ded677ce455ba1acd9d@"

geth attach

I get the following error every few minutes while it tries to sync:


#### BAD BLOCK ######### Chain config: {ChainID: 3 Homestead: 0 DAO: DAOSupport: true EIP150: 0 EIP155: 10 EIP158: 10

Metropolis: 9223372036854775807 Engine: ethash}

Number: 1700000 Hash: 0x279a2890d2b9d9c80da96d052173a5ea281417741aec6bc109efd1e779c2c83c

Error: invalid difficulty: have 11864637714, want 11858882854


In any case it's also only importing a handful of blocks a minute and it's only up to block 1731643 now, when at the time of writing ropsten is up to block 1769191 (so at this rate it'll never catch up).

I haven't found any information on the "invalid difficulty" error.

  • Just started seeing this today as well, is this something new?
    – pfrank
    Sep 29, 2017 at 16:28
  • I installed the latest version of Geth (1.7.0 at the time of writing)
    – ZhouW
    Sep 30, 2017 at 0:17
  • Did you upgrade to v1.7 after the fork? If that is the case then you have invalid blocks from the other fork in your database, it is better to resync again from scratch with the new version.
    – Ismael
    Sep 30, 2017 at 3:47
  • I only upgraded to v1.7 today and synced to the latest block. Strangely I was able to send transactions through geth an hour ago but now they are failing. I'll delete everything in my testnet\geth\chaindata directory and let it sync from the start.
    – ZhouW
    Sep 30, 2017 at 4:20
  • Also having a lot of problems with Ropsten in the last few days, using the Parity nightly builds (as the released version seems to choke on the sync). I assumed it was being attacked again - as well as truffle migrate failing transactions seem to disappear a lot. Sep 30, 2017 at 14:35

1 Answer 1


This error was fixed by #18436.

Try other stable Geth versions (e.g. Geth v1.9.9).

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