already having some ETH on my mist wallet - contributed them a couple of month ago. I can't sync the blockchain as I have to little storage on my computer. Using OS X 10.11.3; ETH Wallet Version 0.8.8. I am only able to sync until 13 % of the blockchain. Sending ETH (to my Jaxx Wallet) did work two days ago (without synchronization of the blockchain) - now, however I can't send any. All transactions I am trying to send at the moment are not working, even though they are shown in my mist wallet transaction history (according to etherscan they were not processed). Any ideas how I could manage to get my current ETH form my mist wallet to some other wallet where I dont always have to sync the whole blockchain? Could it work with myEtherWallet by importing my already owned private key? Any other ideas? Thx :)
Yes. If you have your wallet exported from Mist, you should be able to send from MyEtherWallet 'Send Ether & Tokens' menu.
I am fairly confident that the issue here is nonces.
When you send a transaction a nonce is attached to the signature. This is a unique number which increments each time you send a transaction. It starts at 0.
The idea is that if you resubmit the same transaction it will fail. Only one transaction with nonce 0 can be sent.
With your first transaction it is easy. Mist sets the nonce as 0. With the next transaction it gets the count of transactions (sent from your account) from the blockchain such that it can discern the correct nonce.
As you have not synced the full chain it sees no transactions from your account, sets the nonce as 0, and the transaction fails.
You either need to sync the whole chain or use a servicd that has synced the whole chain.