[Kill Joy]

Introduction

There are a couple hundred thousand unconfirmed transactions on the bitcoin network at the time this thread was written. Click me to see the current amount of unconfirmed transactions. Today I will explain and show you a step-by-step process on why your transactions are stuck on 0 confirmations.

Why does my transaction still have 0 confirmations after 24 hours?

Stuck transactions are usually caused by paying a fee that is too low for bitcoin miners to accept.

What can I do to make my transaction confirm?

There are a few things you can do as the receiver and the sender:

• Sit and wait for the transaction to confirm
  
• Let the transaction time-out (will take awhile)
  
• Contact a miner/pool to mine it for you
  

As a sender you can:

• Attempt to use Replace-By-Fee (restricted to certain wallets)
  
• Attempt a Child-Pays-For-Parent transaction (CPFP)
  

As a receiver you can:

• Attempt a Child-Pays-For-Parent transaction
  

If for some reason you are unable to perform any of the above actions, you must simply wait and hope that your transaction will eventually confirm. If your wallet does not re-broadcast your transaction automatically, you must do that periodically for the network to "remember" your transaction. Most wallets automatically do this for you.

How can I force the network to "forget" my transaction?

Transactions that remain unconfirmed for an extended period of time may be "forgotten" by most nodes on the bitcoin network. This process may take a few days. Reasons a transaction can be "forgotten" are:

• Node Restarts
  
• Mempool expiry times
  
• Mempool eviction (mempool increases minimum fee)
  

How do I get a miner or pool to confirm my transaction?

Some miners and pools offer services to prioritize your transaction. You may contact them and ask if they will take a payment to include your transaction. Many users have linked to https://pool.viabtc.com/tools/txaccelerator/ but it may not necessarily work for you as it has a limit of 100 transactions per hour.

Attempting Replace-By-Fee Transactions

A Replace-By-Fee (RBF) transaction, also known as a double spend, is a transaction that is identical to the one that is "stuck" on 0 confirmations. Please note that transactions that do not use Opt-In RBF will be considered a double spend and will be flagged as such, which may take a long time to confirm still. If you want to get into the technicalities of RBF, refer to my post here.

Three Different Types of RBF Transactions

There are three different types of RBF transactions:

• First-Seen-Safe (FSS) - Requires that the Replace-By-Fee transaction includes the same outputs and inputs (sender/receiver ID) as the original transaction.
  
• Full RBF - A Full Replace-By-Fee means that the transaction is a double spend of another transaction but includes a higher fee; therefore, it replaces the original transaction.
  
• Opt-In RBF - Opt-In Replace-By-Fee simply means that an RBF transaction can only replace a transaction that has been "Opted-In" to allow itself to be replaced.
  

Making A Full Replace-By-Fee Transaction

Making an RBF transaction depends entirely on the wallet you are using. Some wallets will support this option and some will not. Below I will include a list of wallets that support Full RBF and how to go about performing an RBF.

* I highly recommend you use Opt-In RBF, featured further in this tutorial with Electrum, as it is the simplest and easiest one for you to perform.

Bitcoin Core

Download Link from Official Site

In Bitcoin Core Follow these steps:

1. Go to the transaction list
   
2. Right-click the transaction that is stuck
   
3. Choose "Abandon Transaction"
   

If for some reason the option is grayed out, you must restart Bitcoin Core using the -walletbroadcast=0 option. Repeat the above steps after doing this.

If both options listed above fail, you can restart Bitcoin Core using the -zapwallettxes option. This will clear all the unconfirmed transactions. Once you restart it you can start a new transaction, but make sure you include a higher fee.

Bitcoin Armory

Download Link from Official Site

In Bitcoin Armory follow these steps:

1. Go to Help
   
2. Clear All Transactions
   
3. Restart Armory
   

Once you have restarted Armory, you can go ahead and send a new transaction with a higher fee.

MultiBit HD

Website

In MultiBit HD follow these steps:

1. Go to Manage Wallet
   
2. Click on Repair Wallet
   
3. Follow the wizard
   

Once you have completed these steps you can now send a new transaction with a higher fee.

Wallets That Do Not Use Full Replace-By-Fee

This is a list of commonly used wallets that do not use Full RBF:

• Blockchain and most web wallets
  
• Electrum (Supports Opt-In which I recommend you use)
  
• Mycelium
  
• Bitcoin Wallet for Android
  
• MultiBit Classic
  
• Copay
  
• Jaxx
  

Using Child-Pays-For-Parent (CPFP) Transaction

A Child-Pays-For-Parent transactions is when a child transaction spends from an unconfirmed parent transaction and includes a transaction fee which covers both the fee of the child and the parent. These type of transactions are very hard to perform as most wallets do not allow this. A few mining pools will not accept a transaction with a low fee leading to a high fee either.

To do this you must:

1. Make sure your transaction has 0 confirmations
   
2. Send a new transaction with the same amount of coins again
   
3. Make sure you set a way higher fee. Use https://bitcoinfees.21.co/ to determine high fees.
   
4. Send the new transaction.
   

Child Pays For Parent - Blockchain Tutorial

People who use Blockchain can also use Electrum to fix their unconfirmed transactions.

Open Tutorial:

Spoiler (Click to View)
1. Download the official Electrum wallet foundhere. Do not Install it yet. If you already have it downloaded, later in this tutorial just click File > new/restore to create a new wallet. It won't erase your original.

2. Login to Blockchain and go to Settings > Security



4. Go to Backup Phrase



5. Copy and paste all your words (12) onto a .txt file or write them down. Keep these private as someone can steal your wallet with them.



6. Visit https://iancoleman.github.io/bip39/

7. Paste your words.



8. Scroll down to Derivation Path. Copy your Account Extended Private Key. It should start with xprv. Using the xpub key will make your wallet watch only.



Now we will install the Electrum Wallet. People who have already installed Electrum, click File > new/restore to create a new wallet.

9. Select Standard Wallet

[Kill Joy]

CPFP Blockchain Tutorial Continued:

Spoiler (Click to View)
10. Select Use Public or Private Keys



11. Paste your Account Extended Private Key



12. Make a strong password. Remember this!



13. Now go to Tools > Preferences and enable these options like this:



14. Right click "Replaceable" and click Child Pays For Parent.



15. Select a higher fee



16. Sign and broadcast it



Congratulations! You are now down and all you need to do is wait! After 10 minutes my transaction was finally mined. It will look like this:



Any issues with this tutorial, just ask for help in this thread.



Using Full Replace-By-Fee for Various Wallets

• Blockchain and most web wallets
  
• Electrum (Supports Opt-In which I recommend you use)
  
• Mycelium
  
• Bitcoin Wallet for Android
  
• MultiBit Classic
  
• Copay
  
• Jaxx
  

If you use any of the wallets above, you may be in luck! If you wallet is able to export your private key/xprv, then you will be able to perform a Full RBF! Unfortunately new Blockchain wallets are Watch Only, meaning you can't export private keys and therefore cannot perform a Full RBF.

If you are able to export your private keys, this will be a tedious process but it will work! (Picture tutorial to come this weekend)

Follow these steps:

1. Get the private keys for the addresses whose unspent outputs were used in the unconfirmed transaction.
   
2. Import them into Bitcoin Core (see above for a link to the wallet)
   
3. Generate a raw TX
   
4. Sign the transaction
   
5. Broadcast the transaction
   

This should fix your unconfirmed transaction. If you are having trouble, feel free to ask for help in the comments.

Using Opt-In Replace-By-Fee <<<------------ Highly Recommended!!!

There are two wallets that I know support Opt-In RBF, Electrum and GreenAddress. I highly recommend using Electrum.

Electrum

Download the latest Electrum client here.

Open Picture Tutorial (Click to View)

Once you have downloaded and installed Electrum we need to go ahead and enable the RBF function. To do so go to:

Tools
- Preferences then check the box for
- Use dynamic fees (automatically makes sure your fee is adequate)
- Edit fees manually (in the event your transaction does not confirm)
- Select always


The first time you send a transaction it should look like this:


You must make sure that you click replaceable! If the box is not popping up after you changed the preferences, just click the max button and it will appear.

After you have sent a payment you can now click the history tab.


Oh dear! Our transaction is still unconfirmed after a long time. Right click replaceable and click increase fee. *Remember that the dynamic fees should provide an adequate fee and this is in the case that the fee still wasn't high enough.



You can now adjust your fee. Do not click final if you wish to edit it again in the event it that your transaction does not get picked up by miners.



Congrats! You should now be able to successfully get your transactions confirmed.

GreenAddress

Website - Click me!

GreenAddress is an online wallet that uses a plugin with google chrome.

Open Picture Tutorial (Click to View)

Whenever you send bitcoin via GreenAddress, the RBF function should automatically be enabled. If it is not, you can enable it in settings.



As you can see a bump fee button has appeared next to the status box. Go ahead and click that.



You can now select the new fee that you would like to place to get your transaction confirmed faster.

Avoiding Future Issues

To alleviate your pain in the future, there are several things you can do to avoid having these issues.

• Dynamic Fees - Dynamic Fees are calculated by the wallet to provide a timely transaction. Currently a lot of these fees are not efficient enough. In the Electrum tutorial above, I explain how to do this.
  
• Use http://bitcoinfees.21.co/ - You can calculate an optimal fee for your transaction. If your wallet does not support Dynamic Fees and allows you to customize your own, then use this.
  
• Upgrade Your Wallet - If your wallet does not support Dynamic Fees or a custom fee, then I recommend you upgrade to a wallet that does.
  

Conclusion

If you are having trouble with doing any of the above methods, feel free to post in the thread asking for help and stating what you are stuck on. Otherwise feel free to Private Message me. I hope this has helped you in some way or have learned something new. Let me know if you find any errors in this tutorial or have anything to add.


Sources
Spoiler (Click to View)
https://bitcoin.stackexchange.com/questi...ace-by-fee
https://www.reddit.com/r/Bitcoin/comment...lacebyfee/
https://bitcointalk.org/index.php?topic=1701683.0
https://bitcointalk.org/index.php?topic=1802212.0
https://bitcoin.stackexchange.com/questi...for-parent
https://iancoleman.github.io/bip39/

[Cryptic™]

Interesting but can this be abused?

i.e.

Sellers sells someone something so the buyer makes the fee intentionally small so it remains at 0 confirmations for a long time.

The seller is retarted and releases the item after he sees the transaction on the blockchain with 0 confirmations.

Buyer uses RBF and puts a high fee and sends the funds to the buyers alternate address so the seller ends up getting no money?

Edit: Is this what double spend is?

[Kill Joy]

Interesting but can this be abused?

i.e.

Sellers sells someone something so the buyer makes the fee intentionally small so it remains at 0 confirmations for a long time.

The seller is retarted and releases the item after he sees the transaction on the blockchain with 0 confirmations.

Buyer uses RBF and puts a high fee and sends the funds to the buyers alternate address so the seller ends up getting no money?

Edit: Is this what double spend is?

Yes, this is a double spend.

No, using this won't cause scamming in the way you described. The above methods have made it so that new fee payments can only be made if it is for the same sending and receiving addresses.

[Caliban]

Interesting but can this be abused?

i.e.

Sellers sells someone something so the buyer makes the fee intentionally small so it remains at 0 confirmations for a long time.

The seller is retarted and releases the item after he sees the transaction on the blockchain with 0 confirmations.

Buyer uses RBF and puts a high fee and sends the funds to the buyers alternate address so the seller ends up getting no money?

Edit: Is this what double spend is?

you can only increase the fee not change the address i think

also i dont think any sellers accept 0-confirmation payments nowadays

[Patriot]

So if I have a payment pending but I didn't check the Replaceable box when I sent it, will I still be able to edit the fee?

[Kill Joy]

So if I have a payment pending but I didn't check the Replaceable box when I sent it, will I still be able to edit the fee?

You will not be able to. If you had the dynamic fees option enabled, you should be fine as it already provides an adequate fee.

[Fountain Of Youth]

Should I do this for coinbase?

[xDxDxD]

can u decrease the fees this way?

[minimalist]

Works with Mycelium Wallet for Android as well.

[Patzan]

Good thing, I didn't know this thing was there all this time I was using Electrum wallet.

[Mr. Reviewer]

question, can I use this to rush a payment I need to receive?
or does the sender need to proceed with this method?

[minimalist]

question, can I use this to rush a payment I need to receive?
or does the sender need to proceed with this method?

Would need the sender to go through the steps. Watch out for his CPFP tutorial :)

[Kill Joy]

question, can I use this to rush a payment I need to receive?
or does the sender need to proceed with this method?

Like it was already said, the sender must use this method. You can always point him to this tutorial if you would like! Or agree with him to pay a higher fee before he sends it.

[Danny Khalifa]

Does this work on blockchain?
If yes, please let me know