Why on earth didn’t the bcexchanged devs implement wallet conversion? This is not how you develop software!!! If the old data file is not compatible with the next version then the next version has to convert the old data file into the new version. Unbelievable.
If you don’t compile bcexchanged with libdb4.8 you won’t have (wallet file) compatibility with official releases.
But nothing is lost.
You just need a bcexchanged compiled with libdb version 4.8
Follow the instructions here and adapt them for bcexchanged http://docs.nubits.com/nu-raspberry-minting/ and your wallet files will work.
Then I suggest you
- use an official release
- import the privkeys, like @Nagalim proposed[quote=“Hyena, post:5, topic:3846”]
I don’t even know any more why I even bought that pi.
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Because it works reliable and like a charm with Raspbian, comsuming almost no power and needs no heatsink or even fan?
I’m sorry to hear that.
I feel like when MoD asked if you did the upgrade using the official documentation you said no. You want the B&C release to update your pi to libdb4.8 for you?
I don’t think it’s about that. The 4.0.1 does not accept my old 4.0.0 wallet files but it will create new ones without problems.
Ahhh i see, so you want old wallet versions to work in new client versions? A reasonable request for sure.
At this point, all you need is the private keys to proceed though, right? So you just have to open the wallet, you don’t have to download the whole blockchain.
yes, it makes so much sense. I just need the private keys from the old wallet and I don’t even care if there will be one-time full rescan after that to update my balance for the new wallet version. it would be so much easier for the developer to do such conversion than for the user to find a old bcexchange wallet, then dumpprivatekey and then import that private key to the new wallet with the new bcexchange version. I don’t even know what exactly should I do right now to get everything to work again. I am downloading the block chain from scratch to my pc and to my pi in parallel. both are the 4.0.1 versions so my old wallet is probably not going to work on neither of the devices. I don’t know how I can get it to work.
ok the block chain download is taking forever. this is going nowhere
Download 3.0.0 somewhere and try to import your wallet. Don’t worry about the blockchain.
where do I get 3.0.0?
I copied the old block chain to my pc from the pi and now the bcexchange does not start up:
A fatal error occured. B&C Exchange can no longer continue safely and will quit.
EXCEPTION: 22DbRunRecoveryException
DbEnv::open: DB_RUNRECOVERY: Fatal error, run database recovery
nu in Runaway exception
so this is pretty hopeless. I’m not going to get anything to work today. the block chain downloads forever on this slow internet, tomorrow I won’t be here at the pi to fix anything. my only hope is that in the city my other PC still has the old 3.0.0 version so I can get the shares from its wallet to a new wallet version. but I won’t be coming back to my farm then so even though I could get my shares on a new wallet version I cannot start minting on my pi.
Wait so your wallet is stuck in 4.0.0, not 3.0.0?
yes
my wallet is stuck on 4.0.0
There are direct downloads at the end of this OP:
[Mandatory upgrade] B&C Exchange 4.0 has been released
Also, do you have any old backups of the wallet?
ok downloading it., hopefully it allows me open that old wallet and get the private keys. I will then import the same private keys to a 4.0.1 wallet and copy the wallet back to the pi. ideally it would solve my problems 
well this starts to suck, 4.0.0 GUI wallet crashes with an exception in 20 seconds after startup.
edit:
btw block explorer seems to be offline…
https://bcblockexplorer.com/
Yah i was afraid of that. 4.0.0 sucks.
Ok I tried opening an even older backup of my wallet on 4.0.0 wallet GUI and managed to get the private key. However, what surprised me was that 4.0.1 GUI was also able to read that same wallet file and did not throw an exception this time. I might try to copy that older backup to my pi now to see if it also works out. the wallet is from September 2015. should I try the old wallet or still try to import the private key?
edit:
Just to be sure, I used the “back up the wallet” option on the 4.0.1 GUI in my laptop. It gave me wallets with different sha256sum’s than what I had from September 2015. I then copied those new backups to my Pi and so far it has been successfully downloading blocks. It sucks though that every time something breaks the block chain has to be downloaded from scratch. The block chain data structure should be built in a way that it could overcome problems and not require a full re-download at the sight of any problems.
Would a bootstrap service help? Nu did that.
it reminds of the issue i encountered when i once upgraded nu.
the new version could not read the old wallet.
I had to export the priv key.