By Leon Fu Dot Com, 
The Oracle of Austin
Twitter: https://twitter.com/leoncfu
For investors who participated in the Ethereum ICO, it has been a spectacular investment. Even after the disaster with the DAO, Ethereum still trades at a combined value of $14.50 ($13 ETH+ $1.50 ETC), nearly 50 times return. This has been the most spectacularly successful investment most of my friends have ever made.
Unfortunately, the DAO fiasco and hard fork has split the community, and resulted in 2 Ethers, ETH (Hard fork) and ETC (Classic). If you hold any Ethers, you must understand what has happened regardless of whether or not you were involved with the DAO. This is especially important for Ether holders NOT involved in the DAO because the value of their Ethers is now split between 2 coins through no action of their own.
Let’s study the following diagram to better understand what has happened:
Let’s go over the possibilities, so we can understand where we stand.
- If you had DAO token and refunded them for ETH, these Ethers only exist as ETH. They do not exist as Ethereum Classic. You can treat ETH refunded from the DAO as you did before the hard fork.
- The attacker who drained the DAO now has ETC. The Ethers he took from the DAO only exist in Ethereum Classic as ETC. They do not exist as ETH. ETC consists of Ethers that did not participate in the DAO, plus the Ethers that the attacker took from the DAO.
- If you had Ethers straight up in your wallet before the hard fork, you automatically have equal amounts of ETH and ETC. Both chains recognize your Ethers and now you have twice the number of Ethers in the form of ETC and ETH, both worth significant money. Approximately 85% of Ethers were not involved with the DAO. These Ethers are vulnerable to “replay” attacks. What this means is the same transaction involving these Ethers are valid on BOTH chains. A user thinking he is selling ETC, may find that he also sent his ETH with the SAME transaction or vice versa. In other words, a transaction on one chain can be “replayed” on the other.
Of the 3 scenarios, the last one is of great concern to investors who still have plain ETH. We need to be very careful with these ETH’s because sending any transaction as either ETC or ETH may result in sending both ETC and ETH from the same wallet. To guard against replay we need to “split” these Ethers into separate wallets for ETC and ETH. This will protect you from replay since now that your ETC and ETH are in different wallets, the same transaction can’t be replayed on both chains. The following guide describes a process for splitting your Ethers into separate ETH and ETC wallets:
https://steemit.com/ethereum/@pauls/ethereum-fork-step-by-step-guide-to-safely-splitting-your-eth-etc
Personally, I feel this is a bit too technical for most users. You’ll need to understand what is going on, and there’s lots of opportunity to make mistakes even for users who are fairly technical. You can also try to send a small amount of these Ethers to Poloniex to see if they credit you with both ETH and ETC. They should if these Ethers were not involved with the DAO. Early indications seem to point that ETC will survive in some fashion. Hopefully MyEtherWallet and Jaxx will come out with ways to make splitting Ethers into separate ETC and ETH wallets an easy affair as they did with getting ETH refunded with DAO.
To see your ETC balance, there is an Ethereum Classic block explorer here: http://gastracker.io
You can see your balance with this link http://gastracker.io/addr/0xReplaceWithYourAddress by pasting your wallet address in this URL.
Update
Coinbase is not supporting ETC while most other major exchanges are trading ETC. Be very careful out there if you haven't split your ETH into their respective ETC and ETH wallets.
We are in this mess because the Ethereum Foundation did not hard fork properly. They forgot to sever the link completely to the non forked chain by changing the transaction format to make replay attacks impossible.