NavCoin 4.5.1 Hard Fork — What You Need to Know

NavCoin Core announced that the NavCoin blockchain will be undergoing a hard fork at block 2722100 which is approximately this coming Friday - 21 December 2018. All users should update to version 4.5.1 before Friday to avoid network disruption.

For more information about the bug the hard fork is fixing, please read the official notice published to

To make sure you’re ready for the fork, you should download NavCoin Core 4.5.1 from the NavCoin wallet download section.

There have been several questions asked on twitter and discord about how it will effect peoples funds so i thought it was worth discussing in more depth what the fork does and what you need to do.

What does the hard fork enforce?

When NavCoin Core receives a block from the network, it looks at what version of the wallet the block was mined using. After block 2722100, wallets updated to 4.5.1 will only accept blocks mined by wallets using version 4.5.1 and above. Any blocks mined by version 4.5.0 and below will be rejected by the wallet. This is to ensure that all blocks moving forward are mined by the version which is calculating the Community Fund proposal states correctly and no invalid payment requests are included in blocks.

Does the hard fork enforce the other consensus changes being voted on by the network?

There are currently 3 soft forks being voted on by the network (Cold Staking, Static Rewards & CFund Quorum). These consensus changes are not enforced by the hard fork and will continue to be voted on as per normal by the network. Cold Staking & Static Rewards are voting YES by default in version 4.5.1. However if you want to vote against either of these soft forks, all you need to do is reject the version bit in your config file by adding the following line to your navcoin.conf file.

Vote Against Cold Staking


Vote Against Static Rewards


It goes against the NavCoin Core Manifesto to force consensus changes through by hard fork. We aspire to implement hard forks as sparingly as possible (ideally never) and only resort to them in order to fix critical bugs that will cause network disruption or compromise funds security.

Is updating to 4.5.1 mandatory?

Blockchains are organised anarchy, therefore nothing is mandatory. We can’t force you to upgrade to 4.5.1 or accept the hard fork.

What will happen if i don’t update?

If you don’t update to 4.5.1, after block 2722100 your wallet will still accept blocks mined by wallets on version 4.5.0 and below. Since versions 4.5.1 will be rejecting these blocks, two versions of the blockchain will emerge. Think of it like we’re driving down a road at come to an intersection (block 2722100) and people on the old version turn left where as people on the new version turn right. After the intersection the old and new versions will be heading in different directions and will become incompatible with each other.

What happens if i keep staking 4.5.0 or below?

You will continue to create blocks and receive staking rewards, but they will be recorded to the incorrect fork of the blockchain. These new staking rewards will not be able to be spent on the main blockchain. To continue staking spendable coins, it’s advised to update to 4.5.1 before the fork.

What do i need to do with my NavPi?

NavPi’s should auto update when they see the new version on GitHub. However you will still need to login to you device, complete the upgrade procedure and restart the device. If you don’t see the update message on your NavPi it is recommended to perform a manual update to 4.5.1 as soon as possible.

What will happen if i can’t update till after the fork occurs?

Nothing bad will happen, you will end up on the wrong side of the blockchain fork until you update. Once you are able to update, you will need to resync the blockchain or bootstrap the latest version of the blockchain to get back on to the correct chain. Another way to rectify the situation would be to update to 4.5.1 then manually invalidate block 2722100 through the debug window (or the rpc command) and let the wallet resync with the network from there.

What happens to my NAV?

Any transactions which are recorded to the blockchain before block 2722100 will still be valid after the hard fork. As long as you update to 4.5.1 your blockchain will remain in sync with the rest of the network and continue to be able to transact with other nodes. There is no other action which needs to be taken apart from updating.

What if my NAV are on an exchange?

All the exchanges have been notified of the fork and are in the process of updating to 4.5.1 before the hard fork happens. The exchanges have been advised to temporarily suspend deposits and withdrawals on the day of the fork until nominal operation of the network has been confirmed.

What should i do on the day of the fork?

Much like how we have recommended the exchanges to pause deposits and withdrawals for the day, it is recommended that users refrain from sending transactions on the day of the fork until the network is confirmed as operating nominally.

Give me the short version!

To remain on the same blockchain as the rest of the network, exchanges and merchants after Friday 21 December 2018 you need to update to NavCoin Core 4.5.1 as soon as possible. Soft fork & Community Fund votes continue as normal. All funds in wallets and on exchanges will remain valid after the fork. If you can’t update until after the fork, make sure you update as soon as you can and resync to get on the correct blockchain.