FAQ

Where does Sparrow store data?

Sparrow’s home folder is different depending on the operating system:

On Windows, the %APPDATA% folder can be found by opening File Explorer/Windows Explorer, typing %APPDATA% into the address bar, pressing enter. The Sparrow folder will be in the Roaming or Local subfolder.

You can change the home folder using the -d command line flag (see the following FAQ for details). This is useful to store wallets in separate locations, or have a different application configuration for different sets of wallets.

How can I run testnet?

Testnet is a copy of the Bitcoin network where coins have no value. It is ideal for testing wallets and transactions, and it’s use is highly recommended. The simplest way to start Sparrow using testnet is via the Tools > Restart in Testnet menu command. This will close Sparrow, and restart it with a separate testnet configuration in the testnet folder in Sparrow home.

It’s also possible to run Sparrow from the command line (or set up an equivalent shortcut). Sparrow has a number of command line options, for example to change its home folder or use testnet:

For example:

OSX:

Linux:

Windows:

As a fallback, the network (mainnet, testnet, regtest or signet) can also be set using an environment variable SPARROW_NETWORK. For example:

A final fallback which can be useful when running the Sparrow binary is to create a file called network-testnet in the Sparrow home folder (see below) to configure the testnet network.

Note that if you are connecting to an Electrum server when using testnet, that server will need to be running on testnet configuration as well.

When not explicitly configured using the command line argument above, Sparrow stores its mainnet config file, log file and wallets in a home folder location appropriate to the operating system.

Testnet, regtest and signet configurations (along with their wallets) are stored in subfolders of Sparrow’s home folder to allow easy switching between networks.
Once Sparrow is running in testnet, you will need to connect it to server or node that is also configured for testnet. A public testnet server is con figurable from the Server Preferences tab.

Finally, you can receive free testnet bitcoin from a Bitcoin Testnet Faucet like https://testnet-faucet.mempool.co/.

How can I choose where my wallet is saved?

See the section above. You need to run Sparrow with the -d command line flag. Setting this will cause Sparrow to store its configuration and any wallets at the given location. For example on Windows:

This feature allows you to store all Sparrow data on removable media making for more plausible deniability.

How do I increase the fee on a broadcasted transaction?

A transaction’s fee can be increased either by replacing it (RBF), or creating a child transaction (CPFP).

To perform Replace by Fee (RBF), the transaction must:

  • Be in the mempool (not yet confirmed)
  • Have all inputs enabled for RBF (this is the default for transactions sent by Sparrow)
  • Have all inputs from your wallet

If all the above is true, then Sparrow will add a hover icon next to the transaction on the Transactions screen which looks like a hand with a cross above it. You can also right click to ‘Increase Fee’, which takes you to the Send screen with the transaction loaded, from where you can increase the fee (Sparrow may add another UTXO if there is insufficient change).

You can also use CPFP by spending the outputs of the transaction at a higher fee rate.

How does the proxy support work?

When you configure a proxy in Sparrow, it will be used for all external connections. This excludes IP addresses in the 192.168.*.*, 172.16.*.* and 10.*.*.* ranges, so you can connect directly to your node on the local network even with a proxy configured. If Sparrow cannot connect via the configured proxy, but the server is using an onion address, it will start it’s internal Tor proxy automatically. You can disable this behaviour by closing Sparrow and changing the value of the autoSwitchProxy property in the config file.

How do I import my Trezor?

If you have been using the Trezor web wallet at trezor.io, it is likely that when recreating your wallet in Sparrow you need to select the ‘Nested Segwit’ script type. After this is done, import your Trezor xpub by using the Connected Hardware Wallet option.

You can also get Sparrow to search for the script type by using File > Import Wallet…, then click Scan for Connected Devices at the bottom.

Does getting the fiat value leak privacy?

Sparrow gets the exchange rate from the configured exchange rate provider, and then multiplies that with your wallet balance internally. Your wallet balance is never shared externally.

If you have a Tor proxy configured, Sparrow will use it to retrieve the exchange rate. You can also turn it off by configuring ‘None’ for the exchange rate provider in the Preferences.

How do I rename my wallet?

To rename a wallet, first close the wallet in Sparrow. Then go to the wallet file in the wallets folder in Sparrow home, and find your wallet file – it will have the same name, ending in .mv.db. You can now rename the wallet file – just be sure to preserve the .mv.db extension. When you load the file again, the wallet name will be changed.

How can I report an issue?

Please use the Issues on Github to report an issue. If possible, look in the sparrow.log file in the configuration directory for information helpful in debugging.