B&C Exchange v6.0.0 Release – Mandatory upgrade to cancel the grant


This version cancels the recent BKS grant by rejecting the current block 1183900, so it basically makes the node forget all the blocks made during the last week. It will fork the network between 5.x and 6.0 nodes. All nodes will stay connected to each other but on different chains, until the 6.0 chain eventually becomes the best chain for all nodes (it will take some time even if all the shareholders switch now).

If the grant is actually wanted by the majority shareholders they must just keep running version 5.x. This version exists to allow them to revert it if they want to. If there’s no consensus the two chains will coexist.

The 6.0 chain starts when the grant had 43% of the votes. Shareholders must upgrade quickly and mint if they don’t want the grant to still pass on the new chain. And they must make sure they mint continuously in the future to prevent this kind of problem.

After the upgrade shareholders who minted during last week must run this RPC command to clear all their orphaned transactions, otherwise most of their shares won’t be available to mint:


The command can take several minutes to process.


Code changes


6eb168c141be986791979cc3a38bb07f03e395baaf9657ced9f76a26e5797ab5  bcexchange-6.0.0-linux-gitian.zip
ed67615166a7f41101265baef63c3f0fa90bd51346b4abaae31e4ea111628633  bcexchange-6.0.0-win-gitian.zip
e5e2b63f8febefc125cd7fe1279e66af946e55ea87bb452793b2616953c5e4fa  BCExchange-6.0.0.dmg
2a0ab7291f1abcfb5e4571d3b59b99b70e4d9b7f44cf1a4623c22fcfaee1d1de  bin/32/bcexchange
2bc81830b2a67ea9951dbf7e9ef8a929e629a9d7feca2e14e13a504c5c549b15  bin/32/bcexchanged
9f3756f44da1438da1c5f839bac96a0bc923677cbcee739e13f9feff2be726ff  bin/64/bcexchange
4a4e5c2849017445a0a1544abd916030fc3cebc3634e64333a7ec3998cf182d9  bin/64/bcexchanged
a3406ecc14299d5e525bccaf1e9de00e7a7b237081f775c66547ba594ac1a801  32/BCExchange-6.0.0-win-setup.exe
4240d58d6bea0babcbbdfb33fa95e03b68506d3b62f27571148a56c01524551f  32/bcexchange.exe
a214b6b041a6c4ea456c79161e3f6cf61dc3af68bf0105618251a791cf559a31  32/bcexchanged.exe
0c9610a303700d88cc6abd812b49500fed5c3f94e3efb7282dae42ed7e39c70b  64/BCExchange-6.0.0-win-setup.exe
a56cc58dcbb6eea3eef61ae083df9e4875f5ff6e52fdd870107ac09df2a32e96  64/bcexchange.exe
9dd9d901cc24ab88dea64bb382394d0a431528d92719a43c9d43c2e62bac5ff3  64/bcexchanged.exe


The 6.0.0 fork is proceeding well overall. Difficulty is very low at 0.00002865 due to the time gap created the release, so blocks are being found quickly. About 260 blocks have been produced on the 6.0 fork, and there is not a single vote for the malicious grants among those 260 blocks.

Most peers haven’t updated yet, though, so please do that if you haven’t already. The malicious minter or minters appear to have not joined the 6.0.0 fork at this point, though that could change at any time. We need maximum minting power on the 6.0.0 fork to ensure they won’t succeed in passing the grants if they join.

Support for the malicious grants on the 6.0.0 fork stands at 42.6% in the last 10,000 blocks, which is the interval used by the protocol. Let’s push that down!



More than 900 blocks have been minted on the 6.0.0 fork in the last three hours, without a single vote for the malicious grants. This reflects very low difficulty and very high support of the fork from active minters.

Approximately 43% of network nodes are running on 6.0.0.

We still need everyone to upgrade, but the fork is certainly on track for success, with a high degree of consensus.


When the 6.0.0 fork began, support for the malicious grants were at 42.6%. At the moment, support in the 10,000 block protocol interval has been pushed down to 28.6%. However, there has not been a single vote for the malicious grants since the 6.0.0 fork. This means that if voting continues in the same pattern, support for the malicious grants for the 10,000 block protocol interval will fall to 0% within a couple days.

The fork has been a success. The malicious grants have been defeated. BlockShare holders are united on the 6.0.0 fork. Difficulty is rising quickly, which suggests the chain is much more secure than a week ago.

Good work, everyone!


Hello guys,

I’m trying to get this new version to work but I get no incoming connections even after trying all sorts of different ports.

Is there any peer/node list or anything else to help?


Try adding the following to the file bcexchange.conf and restart B&C Exchange Wallet. Please ask if you don’t know where to find the configuration file.


Create or edit bcexchange.conf in:

  • Linux: ~/.bcexchange
  • macOS: ~/Library/Application Support/BCExchange
  • Windows: C:\Users\%USERNAME%\AppData\Roaming\bcexchange
  • Windows (XP/2000/2K3): C:\Documents and Settings\%USERNAME%\Application Data\bcexchange


Currently, in the 10,000 block protocol interval, support for the malicious grants that made the fork necessary currently stands at exactly 0%. That is what we want!


If I replace my old walletC.dat file in this new release I get a crash on startup (tried both windows and macos) . used to work fine with older version of the client.



i need you need to start downloading the chain from scratch after putting your wallet file inside the folder.


I tried already and failed.

Closed the program, deleted all files inside the data folder, placed my wallet8 and walletc inside the data folder, launch bcexchange. Crash

EDIT: it works now after replacing the wallet files with an older backup .