This is copied from the Electrum website today:
July 31st, 2017.
Electrum is a Bitcoin wallet created by Thomas Voegtlin in 2011.
Electrum is distributed by Electrum Technologies GmbH, a company
registered in Germany, using the website https://electrum.org
Electrum users who are not interested in Bitcoin Cash do not need to
worry nor to take any particular action. The following note is only
for users who want to access their Bitcoin Cash (BCC).
“Electron Cash” is a fork of Electrum for Bitcoin Cash. Electron Cash
is not endorsed by Electrum. It is open source, and binaries
(executables files) are available for Windows, OSX and
Android. However, when you run binaries instead of source code, you
have no guarantee that they match the source code. This is why wallet
binaries are usually signed by developers. A digital signature engages
the responsability of the person who signs.
The person who distributes the Electron Cash binaries has decided to
remain anonymous, and uses the fake name “Jonald Fyookball” in order
to sign Electron Cash binaries. Thus, if these binaries contain code
that is designed to steal your bitcoins, the author of the theft will
be anonymous and walk away safely with your funds.
This danger is exacerbated by the fact that the default behaviour of
Electron Cash is to silently copy all your Electrum wallets into its
own directory. Thus, if you run Electron Cash on a machine where you
previously used Electrum, all your pre-existing wallets will be
available in Electron Cash, and you will only need to enter your
password in order to expose your bitcoins to potential theft.
Therefore, users who want to run the Electron Cash binaries should do
it on a separate machine, that does not have their Bitcoin wallet. We
recommend to proceed as follows:
-
Install Electron Cash on a machine that does not have your
Electrum wallets. -
Wait until the BCC hard fork has taken place, and a few BCC blocks
have been mined. -
Move all your Electrum funds to a new Electrum wallet. This will
move only your BTC, and not your BCC, because the BCC blockchain has
replay protection. Wait until the transaction is confirmed. -
Enter the seed of your (now empty) old wallet or private keys in
Electron Cash. Since the BTC have been moved to a new wallet,
entering your old seed in Electron Cash will not put your BTC funds
at risk.
Following these 4 easy steps you will be able to access your BCC
without compromising your BTC.
