Topic: Bad wallet PC, what are my choices? (Read 1870 times)

No. Step 1 and 2 is not necessary in this case.

He uses bitcoin core, the private key be exported without syncing, and be swiped directly with mycelium.

1 and 2 if you dont have paper wallet

You can skip step 1-2 and sweep the private key directly with mycelium.

1. make paper wallet
2. send bitcoin to paper wallet
3. import private key of paper wallet to mycelium android wallet (setting-expert mode  ---->  key, add key(top right key-picture), scan paper wallet private key)
4. import private key of paper wallet to multibit (http://bitcoin.stackexchange.com/questions/14154/how-do-import-a-paper-private-key-into-multibit)

Right, use multibit, www.multibit.org

mmm for a wallet PC i suggest you multibit. I think it is the best. 

Nope, no need to download the entire blockchain. There are probably other hierarchically deterministic ("HD") wallets, which is the behaviour you want from wallets that run on multiple machines. See the link Newar posted for more info on wallets.

Send ALL your coins to a new wallet.

If you don't trust yourself, you can hire an escrow to hold your coins for you, then send it all back when you have your new wallet or PC working. (I'm joking ... but just in case... hehe.)

The assumption so far is that you are using Bitcoin Core. You can get the hard drive from your PC and install it in a new computer, then you can grab all your data and the blockchain as well.

If you have no more use for those addresses it's probably easiest to import wallet.dat at blockchain.info and then make a new transaction to your new wallet. There are other lightweight ones https://bitcoin.org/en/choose-your-wallet . Using a wallet where you 100% control the keys is the preferred way.

Does Electrum need to download the entire blockchain as well? If not I guess I'll have to wait for Multibit HD development to finish...

Anyway, this is an interesting and useful discussion (for me anyway) so thanks for the replies!

Depends what you understand as wallet. The wallet.dat holds private keys and some meta data like labels for addresses, etc.
It comes with 100 pregenerated addresses and as long as you only use those you will not run into desasters. Worst that can happen is that you have not yet revealed the 37th address on PC B so your balance might be off. This could easily fixed with a rescan. Its a pain but not kind of pain that loses you coins.
Another thing are the labels and notes, youd have to make them the same by hand or sync the files via 3rd party tools or by hand in order to keep those identical.
Things will get ugly once you need address 101 on either of the machines, because now core needs to generate new priv. keys. There is no way to avoid drama without syncing the files (via tool or hand) here. Every new TX can make the files get out of sync because of change. A change address is usually a fresh one with core, but if there are no fresh ones left it has to randomly generate a new one. One wrong sync now and the priv. key that controlls the change is gone and so are the BTC.

If you want something like that use a deterministic wallet like Electrum or Multibit HD (not finished AFAIK). That way private key number n will allways be the same no matter where you use the seed.

I also wanted to have my wallet on 2 different computers, I searched around the forums back in the day and the official point of view was that its not good and I shouldn't do it. This might have changed however, with the new client releases. I'm not entirely sure about it.

I don't think the wallets would get synchronized across PCs...Please wait for someone to confirm this whole thing, I'm also interested in this!

That's interesting. I thought that after the blockchain synchronized on both PC's the wallets would mirror each other. I may just export the keys to a blockchain wallet or something. It's just that this is the third time I have issues with my wallet PC and my other option would be storing it in my Surface but I do carry my Surface with me so that's more prone to being lost which is why I wanted redundancy there. Either store the wallet on the PC that turns on if I'm lucky or on the PC that can be easily lost... or go for a cloud wallet and don't even have to worry about the blockchain. Decisions, decisions...

As far as I know it's not good to access the same wallet on multiple devices at the same time.

I am not sure how this works with offline wallets, but if you send coins from computer A then open the wallet on computer B and do some transactions there, I'm not sure how the payment addresses would line up and if the wallet.dat-s would be consistent.

Maybe use an online wallet on one of the computers to store some coins?

Now that I'm going to be doing that, can I load those private keys into multiple PC's so I can access the same wallet from both of them?

You can just load the wallet.dat with bitcoin core, and export all the private keys to a textfile, you don't need to be synced to do that.
Actually, its recommend that you do such an operation while the computer is offline.
The command is called:  dumpprivkey

You can use offline wallet like multibit or you can also import your private keys to an online wallet like blockchain.

Ok; I've never done that but I'll give it a shot. Thanks!

Not really THAT easy, but no problem:

You need to extract the private keys of all your addresses from the wallet.dat file and then import them into multibit. To extract the private keys use pywallet: https://bitcointalksearch.org/topic/pywallet-22-manage-your-wallet-update-required-34028

And Multibit allows a wallet.dat import? I'm checking the site right now and can't find any info about importing an existing wallet.dat.