Log in to Coinfinity on the web portal: https://login.coinfinity.co, or use our mobile app.

Once you are logged in, please go to the “My Wallets” tab. If you have already created an in-app wallet, it will already be listed there.

To add and then confirm the external wallet, proceed to step 2. If your external wallet/address is already listed here, go directly to step 3.#

At the top of the screen, you will find the “Add Wallet” button. Click on it and then select one of the options listed. It is possible to add hardware wallets or software wallets. You can theoretically add addresses from other exchanges or custodial wallets, but you will not be able to confirm them later.

These instructions refer to the Blockstream Green Wallet. Links to the other instructions can be found HERE.

A selection field will open. Select “Other Wallets” to continue. You can use the web portal or the mobile app for this.

In the next step, give your wallet a name. It is best to choose a name that will allow you to clearly identify which of your devices or programs/apps it is later on.

Also enter either your extended public key (XPUB, YPUB, or ZPUB) or a single Bitcoin address, then click “Continue.” We will describe how to do this in the next section.

For the best user experience, add an extended public key (XPUB, YPUB, or ZPUB). It works for both buying and selling Bitcoin. With each purchase, the Bitcoin is sent to a new address, which can be helpful for privacy reasons.

PLEASE NOTE: Unfortunately, we do not yet support Taproot addresses, but we are working on offering this as soon as possible.

Alternatively, you can also use a single Bitcoin address. This only works for purchases and savings plans, and the same address is then used for all transactions.

Open the Blockstream Green Wallet and click on the small gear icon in the upper right corner (a). You will see a selection of menu items. Select “Settings” (b). In the menu that appears, click on the “Watch-Only” option (c).

Under “Extended Public Keys,” you will now see the extended public key in two formats: as a QR code and as a string of characters. You must either copy the character string of the extended public key by clicking on the “Copy” icon (d), or click on the QR code (e) and then scan it from another device (f) (for example, with a webcam or smartphone).

Now you must either click on the QR code logo in the Coinfinity portal and scan the code in some way, or paste the character string from your clipboard. If, for example, you need to transfer the text from your smartphone to your PC, transfer the text to your computer: by emailing it to yourself, via WhatsApp Web, or using Apple Handoff (for Apple devices).

After you have correctly entered the extended public key, click on “Continue” in the Coinfinity portal.

You can now leave it at that and only store the extended public key by clicking on “Confirm later,” or proceed directly with confirming the wallet by going to step 3.

If you choose “Confirm later,” go directly to step 4 – Security clearance via email.

In your Blockstream Green Wallet, you can now close the field with the extended public key and return to the start screen.

Open the Blockstream Green Wallet and select the relevant wallet. A small arrow pointing to the right will appear. Press this arrow to open the wallet (a).

At the bottom right, you will now see the “Receive” button (b). After clicking the button, you will be shown a new, previously unused Bitcoin address.

Now decide whether you want to add this unused address to Coinfinity i), or one of the addresses generated so far ii). Jump to the relevant section of text and skip the one you don't need.

i) You will see the address as a QR code and as a string of characters. You must either scan the QR code from another device (for example, with your webcam or a smartphone) or copy the address by clicking on the “Copy address” button (c).

ii) If you want to use one of the other addresses generated so far, click on the three small dots (d) in the top right corner and select “List of Addresses” (e) from the menu that appears. There you will find a list of all addresses generated for your wallet so far, and you can copy the desired address to the clipboard by clicking on the “Copy” icon (the two small squares) (f).

Now you must either click on the QR code logo in the Coinfinity portal and scan the code in some way, or paste the character string from your clipboard. If, for example, you need to transfer the text from your smartphone to your PC, transfer the text to your computer: by emailing it to yourself, via WhatsApp Web, or using Apple Handoff (for Apple devices).

Once you have entered the address correctly, click on “Continue” in the Coinfinity portal.

You can now leave it at that and just save the address by clicking on “Confirm later,” or proceed directly to confirming the wallet by going to step 3.

If you choose “Confirm later,” go directly to step 4 – Security clearance via email.

In your Blockstream Green Wallet, you can now close the field with the Bitcoin address.

You will reach this step either after adding an address or an extended public key in the Coinfinity portal in the previous step 2 and now want to confirm it, or if you want to confirm a wallet that has already been added.

You will see a random 10-digit string of characters. This is the “message” that you now have to sign using the first address of your wallet. Copy this message or simply write it down for later use. It is important that you do not make any mistakes here. It consists exclusively of lowercase letters and numbers, with no spaces.

To confirm your wallet and assign it to you, sign this message with your Bitcoin address or the first Bitcoin address of your extended public key.

To do this, you must continue to perform the following steps:

Open the Blockstream Green app and select the relevant wallet. A small arrow pointing to the right will appear. Press this arrow to open the wallet (a).

At the bottom right, you will now see the “Receive” button. After clicking the button, you will be shown a new, previously unused Bitcoin address (b).

Click on the three small dots (c) in the top right corner and select “List of Addresses” (d) from the menu that appears. There you will find a list of all addresses generated for your wallet so far. To sign your extended public key, follow section i); to sign a specific address, follow section ii).

i) Scroll down to the first address listed here (#1). This is the first derived address of your wallet and is therefore often associated with the extended public key. Then click on the small “signature” icon next to the relevant address to generate a signature for the extended public key (e).

ii) Search the list for the Bitcoin address you want to sign. This is the one you created in the previous step in Coinfinity. Then click on the small “Signature” icon next to the relevant address to generate a signature for this address (e).

A new small window will then open with the heading “Authenticate Address” (f).

Then type in the large text field (f). You must now paste the 10-digit message from the Coinfinity portal into this field (g). Copy it or simply write it down.

Once the message has been inserted correctly, click on the “Sign message” button (g) below the text field.

You will now see a long string of characters. This is the signature you need to enter in the Coinfinity portal to confirm your wallet/address.

To do this, copy the entire string by clicking on the “Copy Signature” button (h) and make sure you paste it correctly into the portal. Please do not write this string down, as this is prone to errors. Transfer the text to your computer: by emailing it to yourself, via WhatsApp Web, or using Apple Handoff (for Apple devices).

After adding the signature in the Coinfinity portal, click on “Confirm.” If everything went well, your wallet or address is now created under “My Wallets” with the label “Confirmed” and can be used.

If you see an error message (“Please enter a valid signature”), there was an error in one of the intermediate steps. What can happen?

In any case, try again and make sure you can definitely rule out all errors.

After you have added your wallet—regardless of whether you sign it immediately or add the signature later—we will automatically send you an email with a six-digit confirmation code.

PLEASE NOTE: This verification is required for every external wallet you register with Coinfinity. You cannot use the wallet without entering this code.

The code is valid for 10 minutes. Before entering the code, you must confirm that the wallet is a self-hosted wallet. To do this, check the box in the interface.

Then enter the six-digit code from your email in the input field.

Click on “Add Wallet” to complete the process.

After successfully signing and confirming your wallet, you will see all signed wallets or addresses listed in the “My Wallets” menu. For each purchase, you can now choose from the confirmed wallets/addresses.

IMPORTANT: If you interrupt the code entry process, the wallet will still be displayed in your overview, but will remain listed as “Waiting for code.”

If you decide to use the wallet a little later, you will have to request a new code, as the original one will have expired after 10 minutes.

If you receive an error message during the process, check the code or request a new one if necessary.