Geth cannot send transaction becuase of unknown account

Question

I've successfully connected to a local ethereum node with geth. I'd like to send a transaction from one account to another but I get errors that the accounts are unknown, even though the one account has a balance.

 ❯❯❯ geth attach ws://127.0.0.1:65130/ext/bc/C/ws
Welcome to the Geth JavaScript console!

instance: v0.8.4-rc.3
coinbase: 0x0100000000000000000000000000000000000000
at block: 0 (Wed Dec 31 1969 18:00:00 GMT-0600 (CST))
 modules: eth:1.0 net:1.0 rpc:1.0 web3:1.0

To exit, press ctrl-d or type exit
> eth.getBalance("0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52Fc")
5e+25
> eth.sendTransaction({from:"0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC", to:"0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FD", value: web3.toWei(0.05, "ether")})
Error: unknown account
        at web3.js:6365:37(47)
        at send (web3.js:5099:62(35))
        at <eval>:1:20(15)

Why is geth complaining of an unknown account when I've verified the account has a balance? How can I use geth to send a transaction using this account?

Answer 1

Turns out I had to import and unlock the account in order to be able to send a transaction

> personal.importRawKey("56289e99c94b6912bfc12adc093c9b51124f0dc54ac7a766b2bc5ccf558d8027", "lol")
"0x8db97c7cece249c2b98bdc0226cc4c2a57bf52fc"
> personal.unlockAccount("0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC", "lol", 300)