Question about bitcoin wallets.

[Colecf]

If you lose the wallet.dat file, is there any way to recover it? Are you essentially deleting money if you delete it? And what's to stop you from duplicating the file to duplicate bit coins?

[Mike Christ]

The wallet.dat stores all the keys to your Bitcoin; you never actually store bitcoins, you only store data that says "you can spend X amount of Bitcoins".  It's more like a ledger.  If you lose your wallet.dat, you lose access to those Bitcoins to spend, effectively the same as sending your gold on a rocket into the depths of space never to be seen again.  There's absolutely no way to recover it, unless you made a back-up, or you're using electrum and copied down the seed to your wallet.  However, if you made a backup, it's safe to delete it.

[naphto]

If you send a bitcoin in the network, it will be checked by the miners to prevent double spend. And it will update the amount in the wallet.
You can't duplicate bitcoins, because you don't really own them. The network assume and check that you own them.