Version 2.3.1b

Minor release.

Change log

• Fix staker using too much CPU after the previous blockchain upgrade.
• Halve Max Reorganization Depth.
• Minor code optimizations.

Updating is optional, and only recommended if you are staking and you want your computer or node to be less wasteful in its CPU use.

To update your desktop wallet, you just need to download the archive, stop your wallet and let it fully shutdown, and then copy the executable files to replace the ones you had installed already.

If you are making a fresh installation and you want to synchronize faster, you can download a blockchain snapshot from https://www.bitc2.org/Snapshot_latest.zip
If you choose to use that, read the ReadMe.txt that is included in the .zip file for instructions.

Version 2.3.1

Version 2.3.1 change log:
These two bugs were introduced by v.2.3 and fixed in this version:

• When a node's adjusted clock was off, which can be caused by peers, then that node could easily have rejected valid blocks that it thought had a timestamp too far in the future, causing it to fork off to its own chain if the node created a block afterwards. This was fixed by changing to check if the node's own clock OR the adjusted clock can accept the block from now on.
• Fixed an uninitialized staking related variable that sometimes caused staking to fail or other erratic behavior, such as crashing.

Other changes:

• Added cs_main locks that were missing and that could have caused multi-threading related erratic behavior, such as crashing.
• Increased logging especially if debug mode is on.
• When creating new blocks, the staking algorithm now trusts the computer's own clock instead of the adjusted clock that can be affected by peers.
• Removed obsolete v2 staking code.
• Limit worst peers adjusting time.
• Added a second check against invalid timestamps.
• Added -maxtimeadjustment variable. It is recommended to set maxtimeadjustment=0 at bitcoin2.conf if you trust that your computer's clock is accurate to the second. Thus you trust your computer's clock and don't accept adjustments from peers.
• Miner optimization, including reducing the number of stale blocks created.

Updating your desktop Bitcoin 2 Core wallet or masternode to this version is optional if you already had the v.2.3 or newer, but it is highly recommended, especially if you are staking or your node has crashed after November 1 2020.

Version 2.3b

Change log

• Fixed a new bug introduced in v.2.3 that caused some users to be unable to sync from scratch past the genesis block on at least Linux 64-bit systems with the v.2.3 wallet and just reported a segmentation fault when trying to launch it on a fresh installation.

While the problem was only reported to affect freshly installed Linux 64-bit wallet trying to sync from scratch, we updated all the binaries of v.2.3, except for Windows anyway. Skipping Windows because the Windows wallet was unaffected by the problem.

Updating is optional, and only recommended if the wallet launch problem affects you.

v.2.3 release now has the updated binaries.

Version 2.3

Version 2.3 change log:

• Stopped reserving a new key unnecessarily when creating a new block.
• Improved ActivateBestChain and changed how it relays blocks.
• Added a checkpoint
• Slightly reduced logging with debug mode enabled.
• Incremented protocol version.
• Advanced use only: Added an bitcoin2.conf option to send a third of the stake reward to an address, instead of only supporting a specified amount. (To use it, put 3 instead of the satoshi amount.)
• Warn if sending to an address starting with a 3 - In the send dialog, check for multisig or segwit address in case of accidents. Warn if trying to send to such an address.

The below changes will apply once the blockchain reaches the mandatory upgrade block number 1141660:

• The first and only scheduled BTC2 block reward halving happens and soon after that upgraded peers will disconnect from those that have not upgraded.
• Difficulty will be adjusted every block instead of every 10 blocks.
• Difficulty adjustments were optimized so that the average block time will once again be 1 per minute instead of the current average speed of roughly 3 blocks per 4 minutes. This adjustment means that after the halving, the amount of BTC2 generated per day will be roughly 66.667% of before, instead of only 50%.
• 129600 blocks (roughly 3 months) after the upgrade, the new amount created per block is reduced by 0.01 BTC2 every 43200 blocks (roughly 1 month) until the minimum, final reward of 0.2 BTC2 per block is reached. For masternodes, each such reward reduction is 0.0025 BTC2 and for stakers, 0.0075 BTC2. So the ratio was not modified. We made a chart at https://www.bitc2.org/bitcoin2-block-rewards that shows in detail the upcoming block reward structure.
• Some new changes start applying to our custom Proof of Stake algorithm. The most obvious change is that each block’s time stamp has to be at most 25 seconds in the future and not earlier than previous block time, which should help stakers to generate less orphan blocks as it will be less likely than before that more than 1 UTXO will be eligible to stake at any given time.

This is a mandatory update.

All Bitcoin 2 wallets, including masternodes need to be updated in order to stay in the correct chain past block 1141660. (~September 17 2020).

Windows 32-bit support has been dropped, at least for this version. Almost nobody runs the 32-bit version of Windows anymore.

To update your desktop wallet, you just need to download the archive, stop your wallet and let it fully shutdown, and then copy the executable files to replace the ones you had installed already.

If you are making a fresh installation and you want to synchronize faster, you can download a blockchain snapshot from https://www.bitc2.org/Snapshot_latest.zip
If you choose to use that, read the ReadMe.txt that is included in the .zip file for instructions.

Version 2.2.4

Version 2.2.4 change log:

• Minor staking CPU efficiency optimization.
• Stopped creating new keys for no reason when generating PoS blocks.
• The 10004 BTC2 that was stolen along with other major cryptocurrencies from the third party service Simple Pos Pool is soft-locked in this version. If you don't support the lock, simply don't update your wallet. The more nodes that update, the stronger the lock that prevents the thief from moving those funds.

Updating your wallet to this version is optional if you already had the v.2.2 or newer.

Version 2.2.3

Version 2.2.3 change log:

• Optimized a few staking related variables that were previously wrongly set in a way that made the code to not try all possible staking times.
• Fixed some potential crash scenarios.
• Added a block checkpoint.
• Fixed: Masternode ping was not being checked against the active chain.

Updating your desktop Bitcoin 2 Core wallet to this version is optional if you already had the v.2.2 or newer, but it is recommended, especially if you are staking because this version has proven to stake better. Updating your masternode is recommended only if your masternode that is running an older version has problems.

Version 2.2.2

Version 2.2.2 Change log:

• Fixed some concurrency issues in ActivateBestChain(). This fixes a scenario where a staking wallet was unable to move on to the chain with the most work quickly without restarting the wallet. This fix also improves staking performance, especially for stakers who noticed this issue.
• ActivateBestChain() now only relays the new tip block to peers.
• Optimized the miner to find a stake first before processing transactions.
• Optimized the miner to be faster to stop trying to create a block with the previous block height’s parameters once a new block comes in.
• Added a new optional feature that sends a portion of all stake rewards or the whole amounts without a fee to an address that can be defined in bitcoin2.conf. This feature is meant for advanced users only.
  Usage:
  sendrewardcutsto=BTC2Address
  sendrewardcutamountinsatoshis=60000000
• New check to see that the stake transaction does not include more than 10 outputs.
• Removed memory consuming pointless variables and containers inherited from the forked codebase that were pointless in their code too.
• Optimized staking to not try past times. As per our tests, past times never staked successfully in this new staking protocol.
• Updated wallet’s min tx fee to the correct rate of 0.00003000 BTC2/KB, down from 0.00003200.
• Minimum staking UTXO is now 0.01 BTC2. Previously no minimum was set.
• importaddress supports addresses starting with a 3 again and importing a wallet from a wallet dump is now faster than in the previous v.2.2 - 2.2.1 wallet versions.
• Added a block checkpoint.
• Added a warning to the help text of dumpwallet command and the file created by it now says that it is your wallet in the file name. This is to ensure people know what the file is to ensure they don’t send it to anyone else.
• Added a warning to the help text of dumpprivkey command.

Updating your Bitcoin 2 Core wallet to this version is optional if you already had the v.2.2 or newer, but it is very highly recommended, especially if you are staking because this version has proven to stake better. Updating your masternodes is optional.

To update, you just need to download the archive, stop your wallet and let it fully shutdown, and then copy the executable files in the bitcoin2-bin folder to replace the ones you had installed already.

Version 2.2.1c

This is just a partial release of the most current wallet version, and not a full release. Updating to it is optional but recommended especially if any of the below 3 changes might be useful for you.

Version 2.2.1c Change log:

• Added instructions to multisig address creation error message.
• Re-allow trying to import an address starting with a 3.
• Fixed a potential issue that could in theory cause the wallet to temporarily fork into the wrong chain.

To update, you just need to download the archive, stop your wallet and let it fully shutdown, and then copy the executable files in the bitcoin2-bin folder to replace the ones you had installed already.

Version 2.2.1b

Version 2.2.1b Change log:

• Optimized performance and reduced wasted CPU cycles. This fixed various issues that started after the new staking protocol was activated. Such as the wallet failing to broadcast a transaction or forking off to the wrong chain.
• Added block checkpoints.
• Fixed staking icon showing as gray even while you were staking.
• Fixed fee rounding error while using the minimum fee, and set the minimum TX fee to 0.00003 per KB. This rounding error could have caused a transaction to be stuck before enough stakers updated to this version. (Which happened already.)
• Updated the new Mac OS wallet with icons that use the new logo and fixed the pink borders issue.
• Fixed masternode starting/syncing problem of v.2.2 that occurred after the Staking Protocol Upgrade came into effect.

Updating your Bitcoin 2 Core wallet to this version is not mandatory if you already had the v.2.2, but it is very highly recommended, especially if you had any problems whatsoever.

It is also highly recommended to update all your Masternodes' wallets to this version, especially those that you were not able to start successfully.

To update, you just need to download the archive, stop your wallet and let it fully shutdown, and then copy the executable files in the bitcoin2-bin folder to replace the ones you had installed already.

After upgrading your Masternode and your desktop wallet, you should go in the Masternodes tab on your controller wallet and click to Start the upgraded Masternodes after they are reported as "missing".

File type of the Linux 64-bit version now appears as application/shared-lib on some systems. This is because the executables are hardened for extra security. The original Bitcoin Core executables appear as application/shared-lib on those systems too. You can launch it from the command line with ./bitcoin2-qt or create a shortcut or a shell script that simply launches it.

Version 2.2

Version 2.2 Change log:

• Upgraded the staking system and improved staking efficiency.
• Updated QT to 5.9.7. This can fix the Mac version start-up problem for Mojave and High Sierra users. It also means that Bitcoin 2 Core software starting with v2.2.0 will no longer run on MacOS versions older than Yosemite 10.10.
• Upgraded depends.
• Fixed a rare wallet crash scenario that could have happened while staking if one was beaten to the block and validating their created block.
• Removed Qt4 build support and code fallbacks.
• Fixed missing block explorer icon.
• More than 99 confirmations will be required before coins can be staked.
• If all other conditions are met, staking now begins after the wallet receives its first coins that can be staked without having to restart the wallet.
• Changed the minimum transaction fee to 0.00003200 BTC2 per KB.
• Removed explicitly unused transaction comparators that sometimes could have caused transaction timestamp display issues.
• Completed the changes to claiming from the fork.
• Started using the clock5.png icon when a transaction is almost confirmed.
• Implemented block spam filters to prevent the possibility of spam attacks (AKA. denial of service) to one by one crash or slow down nodes that the attacking peer could connect to. No spam attacks were known to have happened on the BTC2 network, but this ensures that they will not in the future either.
• Minor optimizations.
• Our new staking protocol fixes PoS v3 algorithm vulnerabilities. We added time-tested solutions that have not been able to be exploited and extra checks and rules of our own to ensure that no one can gain more staking power than someone else who has an equal amount of coins. We are one of the first Proof of Stake coins to truly fix these vulnerabilities. Many are still vulnerable, including those that just did a basic patch that only served to increase the cost of a potential attack.
• Removed the stretched Windows installer icon.

Updating your Bitcoin 2 Core wallet to this version is mandatory. That includes upgrading all your Masternodes. After enough nodes have upgraded to this version, a new staking protocol will be activated and the old nodes that fail to upgrade their wallet before that will end up forking to the wrong chain. Update: The Staking Protocol Upgrade happened on August 23 2019.

To update, you just need to download the archive, stop your wallet and let it fully shutdown, and then copy the executable files in the bitcoin2-bin folder to replace the ones you had installed already.

After upgrading your Masternode and your desktop wallet, you should go in the Masternodes tab on your controller wallet and click to Start the upgraded Masternodes after they are reported as "missing".

If you want to synchronize faster, you can download a blockchain snapshot with transaction indexing enabled from https://www.bitc2.org/snapshot-August-23-2019.zip
If you choose to use that, read the ReadMe.txt that is included in the .zip file for instructions.

• File type of the Linux 64-bit version now appears as application/shared-lib on some systems. This is because the executables are hardened for extra security. The original Bitcoin Core executables appear as application/shared-lib on those systems too. You can launch it from the command line with ./bitcoin2-qt or create a shortcut or a shell script that simply launches it.