Bitcoin Forum

Hello guys I am nakamura12,
I would like to share this tip on "how to enable Two Factor Authentication also known as 2FA by using address only" to newbies and other forum members that didn't know how to enable 2FA. To those who already know how can also help (if you want to). At the bottom is an explanation why you should make a back up of the secret key of the 2FA.

Before I start, You must download and install an Authenticator in your mobile device or in desktop if you know an authenticator that have desktop version. There are Authenticator that you can use.

The Authenticator used in this thread is Google Authenticator since it is what I used before and this is only an example and the point or goal of this is all about how to enable 2FA. It's up to you on what 2FA authenticator you will use.

1] Open the website where you want to enable 2FA and log in your account, after that open account settings. In my case refer to image below where I can see the 2FA in my accounts settings. My case is in einax website. (Note: I'm not advertising their website and I use it for example only)


2] Click the Two-Factor Authentication as shown in image above and you will be redirect to new page where you can see the address needed to enable 2FA. Refer Image below.



3] Copy the address that is provided from the website.














2FA - Important Precautions with Google Authenticator (https://bitcointalk.org/index.php?topic=3178131.0)

Other Authenticators you can use:
Best 2FA applications to use. Open source, free, secure. Better than Google's (https://bitcointalk.org/index.php?topic=5451585.0)

REASON: You can't get code again from another device if you lose your mobile device but by doing the same guide with the same secret/address key you use in google authenticator that you backed up then you don't have to worry.

Feel free to ask questions or correct my mistakes If i have mistakes in my guide.
In my case I enable 2FA in my account in einax.com to be an example on how to enable 2FA.

Don't forget to backup secret key because it's very important when you lose your device. Make sure it's well written on the piece of paper or make a backup copy in your USB device or PC.

I just want you to add this method because the android google authenticator doesn't have a backup feature unlike in laptop/PC.

Got it thanks, I'll update it right away.

Please correct me if I'm wrong:

• There is no 2FA option for Bitcointalk.
• Google authenticator 2FA (I think it's called time based 2FA?) is flawed as it assumes your computer is clean at the time of 2FA activation, if there is some kind of malware on your computer it could simply steal your 2FA key (secret key)

Do we really need a tutorial like this here? Almost every site who applies 2FA have a guide on how to do it, and you can search this quite easily on the web.


1. He doesn't talk about 2FA on this forum but in general.
2. What kind of malware can do that?

You should never use the same machine to log in and store 2FA keys. This is the whole point - your 2FA key is in one place, and your login/password in a completely different place. If your PC will be breached and login information was stolen - your account is still safe, and if you lose your device - auth codes are useless because nobody knows login/password or even what they suppose to open.

Even though you should not use the same device to get OTP and log in it is relatively safe to neglect this rule on mobile, since mobile environments often use means to isolate mobile apps from each other (Android phones are slightly more vulnerable compared to iOS but still mostly safe to use).

Stay safe!

You're not wrong nor right. I'm not telling or referring that there's a 2FA in bitcointalk it's just an example.

Yes, but not for who already know on how to do so and some newbies doesn't know yet so I'm sharing this for those real newbies.

You got my point on this one.

I have already downloaded Google Authenticator (https://play.google.com/store/apps/details?id=com.google.android.apps.authenticator2&hl=en&rdid=com.google.android.apps.authenticator2) and it seems it only works on smart phone. I have used the email which is connected to my phone.

Now it work even if I used my PC still ask for a 2FA google authenticator. However, I am only picking some website that should be used with 2FA google authenticator for it will be annoying also if it will be applied to all websites.

If you think that you're doing something serious on that site then you can enable the 2FA, it isn't necessary to use this from everything. Just choose a site that seems substantial such in trading sites that we mostly use and sometimes leave our coins for a while.

I just know this. Thanks.

This is simplified enough , any newbie that have further questions can ask ,I'm sure many people are here to respond approximately.

It should also be noted that the 16Digits code should be kept safely

I know you're trying to help but it is noted already, I guess you didn't read all of it. Secret key/address key is the 16digit code what you want to be noted. BitMaxz already mention it .

Consider this scenario:
1. Your computer is infected with malware.
2. You set-up account on exchange and enable 2FA.
3. You fund your account on exchange from another device/ hardware wallet - you think you're safe, you're using hardware wallet and exchange account is secured by 2FA
4. After few days you find out that someone stole your coins from exchange - how this could happen???

Well, the answer is simple, points 1&2 - you received 2FA secret key on infected PC, so 2FA won't stop robbers.

It won't happen unless you know how to keep your computer safe (at least) from malwares. If that someone trying to steal your coins from your exchange account should at least need the exchange account (Username and Password) and the private key of course for 2fa. Changing the password after enabling 2FA is important as the saying goes "PREVENTION IS BETTER THAN CURE".

But 2FA job is to secure you account against malware, it doesn't protect from hacks etc. contrary to what many people believe.

Yes, it is. Let's just say that it's not a perfect security but it also help.

I just want to add about my experience with 2FA Authenticator which gives me a problem (well because this was new to me), I wanst able to log in however I try to encode my code and discovered that the time settings in my phone is different from the net. i just changed my time settings to set automatically and viola! its good. Just sharing, maybe some can meet this problem.

This is also happening to me before I always tried to use the generated code from 2fa but it doesn't work and I notice that my laptop time is not the same as my local time so I just edit and update the time and after that, I sync it from google authenticator and it works again.

So I advise to other users who experience the same thing you should always check your time if it's updated or not.

I don’t know how anyone, but I don’t like Google Authenticator, problems with it alone, the code is not correct that time, and I came across a similar program but many times better is Authy, everything can be done easily and backups easily ;)

I know that but it doesn't mean that it is best to use google authenticator, there are other people that also use google authenticator and this thread is to show on how to enable 2FA. One thing I can tell is it depends on you what authenticator you would use.

Nice guide OP but imo I think Authy is a far much better alternative to the once popular Google Authenticator because

• Authy automatically backups 2FA data which google can not
• Authy has several ways of getting back onto your account unlike limited ways of Google 2fa
• Lastly the interface is user friendly too :)

Being 2FA a great enhancement in security, one needs to consider the security features related to the 2FA itself. Google Authenticator is typically installed on your phone or table, and the account is tied to a single device.  If you lose the device or it is damaged, you had better have your backup codes handy, otherwise you are going to be in deep trouble to access the accounts you’ve tied the 2FA to, and will need to be stressed-out contacting customer support of exchanges and so on. Switching devices is also non-trivial.

Authy on the other hand is multi-device (even desktops/laptops), it has an encrypted backup on the cloud that you can restore from onto another device, and has an easy process to allow you to move your 2FA access from one phone to another should you change phone. All in all, I find Authy to be safer from the user’s perspective, although one could argue that you may not want an encrypted backup on the cloud.

You're right,  I also had authy in my mobile device. I installed two 2FA authenticator which is Authy and google auth, the google auth is very easy to use and simple but the problem is that you cannot back up the secret key using the app unless you wrote the secret key in a piece of paper. Authy is good and when you lost/stolen your phone and someone try to access the authy and there is a pin before you can unlock and use the authy.

BUMPED THREAD for NEWBIES!

Advice newbies to use Google Authenticator application nowadays is no longer good. It brings risk to newbies.
2FA - Important Precautions with Google Authenticator (https://bitcointalk.org/index.php?topic=3178131.0)

You can use other compatible 2FA.
Best 2FA applications to use. Open source, free, secure. Better than Google's (https://bitcointalk.org/index.php?topic=5451585.0)
I only see Google Authenticator as an app choice, can I use other 2FA apps? (https://support.binance.us/hc/en-us/articles/360056220154-Two-Factor-Authentication-2FA-Guide-Troubleshooting#h_01GKHX3G7J1F542BD2MQJDFA1H)

This thread is all about how to enable 2FA and not the Authenticator itself that's why I edited the title. I understand your point but you missed the goal of this thread and how old this thread is.

Edit more please.

You only wrote about Copy and paste the Address code to activate 2FA.
You did not write about Copy and Paste the Address code to somewhere as your 2FA backup. Backup is needed for 2FA recovery later or to import it into a new device.

Forget about backup is very bad in cryptocurrency, for your wallet and for your 2FA.

It is at the bottom which it is mentioned and I quoted the post and added at the bottom and an explanation. I think that you missed that one. I already included that one before you made a post about Authenticator.

Better than don't have that reminder at all but I don't think it is good enough.

The reminder should be one step before a step to Copy the address to activate 2FA on the application.

Reasons are because if you don't do it before the activation step, how do you have that code for backup?

If you don't make backup first, later you will have no code to backup. If you want to backup, you have to Disable 2FA and Enable it again to get a new Address code for your new activation time.

Your topic does not have a guide for 2FA deactivation and re-enable it with new 2FA activation code.

If your device is no longer usable and you did not back up 2FA, you only can open a support ticket and wait for exchange support. They will ask you to provide documents to verify your identity that is time wasting and not comfortable.

 Always backup a code you use to activate your 2FA.
You need it to recover your 2FA later or to import it on other devices.
Always backup in cryptocurrency.  

if you want a more complete topic, you can add it here, and the OP can add it if it's relevant. very simple I think.
every time you enable 2FA, the website will automatically give a warning to copy the backup code to help us in case of problems in the future.
actually if beginners follow the exemplary procedure there will be no too complicated mistakes.