How to prove a payment
OutProofs are the preferred way to prove a payment to an address.
Go to the History tab. Right click on the transaction that includes the payment you want to prove, then click Create tx proof. Select “Prove payment to an address”. Add a message if required, and make sure to select the correct destination address.
To export your proof as a PGP-like message, click Get Formatted Proof. Note that only Feather Wallet currently supports this format. If the recipient does not use Feather Wallet, click Get Signature.
To verify the transaction proof the receiver needs the Signature, Address, Message and Txid. A formatted proof includes all these details.
Transaction Secret Key
Some services may require you to provide a “transaction secret key” to prove a payment. To obtain this key, go to the History tab. Right click on a transaction → Show details. Click on Copy Tx Secret Key.