Bitcoin Forum

I have a wallet I created with Electrum on a device that has never connected to the internet. I have sent bitcoin to an address in the wallet, but obviously the transaction does not show up. Is there anyway I can add a transaction to the wallet other than using the internet? For example, I have the tx file that I created with electrum (The bitcoin I sent to the new wallet was on another Electrum wallet). Can I somehow add that to the wallet's tx history?

I don't think if it is possible. The whole point of an offline wallet is that it has no Internet connection. Electrum is a lightweight wallet so it doesn't synchronise fully with the blockchain but connects to the other nodes. Create a watch-only wallet on an online computer, it will be much easier and more secure. I wrote a tutorial on that some time ago.

https://bitcointalk.org/index.php?topic=3774520.msg37162163#msg37162163

A less technical solution might simply be to look up the address you want to watch and bookmark it (I do that for a few addresses). So for example, if you bookmark https://blockchain.info/address/XXX, where XXX is the address, you just visit it on your bookmark (I name them too), and it lists balance, transactions. You can use blockchair to look up bech32 addresses.

Based on my understanding on OP statement. He wants to view his updated balance without using internet in his Electrum wallet which I wonder what is his purpose. Technically that bookmark trick is not the answer to OP question. And I believe there is no way to update the Electrum Balance unless it will connect on the internet.

Cold wallet should only be for sign transaction and even some say it is possible to upload transaction history from watch only wallet it certainly is not advisable. I suggest you to use that cold wallet just for sign transactions, and by using Master Public Key create watching-only wallet where you can always see your updated BTC balance without any risk for your private keys.

In your case, your wallet device basically serves as holding your private key (offline) and allowing you to perform transactions associated to addresses linked to your wallet address. On the other hand, bitcoin balances are constantly updated on the network whether you are offline or not. So to answer your question:
1. You can receive payments into any address in the wallet whether you are offline or not.
2. The transaction history gets updated as soon as your cold storage device gets connected to the bitcoin network.

Hence you definitely need the internet.

how do I do off-line signing of transactions then?

have a watch-only address/wallet on an online device for monitoring/retrieving unspents
use it to create unsigned rawtx then use usb as an intermediary between online and offline devices
sign with your offline wallet and pass it back to online device for broadcasting
but using this method, some people would consider the address is no longer as cold storage (because of usb use, physical contact)
for completely air gapped cold storage, each device should have camera to scan QR code of transaction 

Preferably you would use a computer/laptop that's never been online, something like a fresh linux install.

For instructions on how to do this using Electrum, click here (http://docs.electrum.org/en/latest/coldstorage.html).

Other wallets have similar instruction manuals you can find just by using Google.

I did exactly what thirdspace did, I exported the unsigned tx file, put it on a usb flash drive, and opened it on my offline computer. I loaded the raw tx, and the Sign button has been greyed out.

I did that. I'm using TAILS with the persistent mode feature

it is because your offline wallet does not recognize the transaction you just gave it to sign, there must be something wrong with the unsigned tx that you created.
first make sure you are using the same Electrum version on both computer and make sure it is the latest version which is currently 3.1.3 https://electrum.org/#download

I'm using electrum version 3.1.3 to create the unsigned tx (in Debian GNU/Linux) and electrum 3.0.6 for the offline wallet in TAILS linux. Problem is I cannot update electrum as it be deleted upon shutdown

I reinstalled 3.0.6 on the computer that has the watch only wallet, and i created another unsigned tx; that didnt work also.
EDIT: I ran electrum 3.1.3 on the computer with the offline wallet, the same as the watch only, and still, the sign button is greyed out.

Did you check whether you have the correct wallet file opened on your offline machine?

You might also try to look at the addresses. Does your offline wallet contain each address used in your transaction?
If you can not find those addresses in the address tab, you might try to create another bunch of key pairs with this command (in 'view' -> 'show console' -> 'console' tab): for i in range(5): createnewaddress()

what is the wallet type under wallet menu > information?

edit: i mean wallet type of the offline wallet.

Standard.

In electrum, if you load a transaction that references an address that is in the wallet, it will be highlighted. When I load the transaction, the address is highlighted, indicating that I have loaded the correct wallet file.

Did you create the watch-only wallet using your master public key (xpub) or using specific addresses?

Single address. Perhaps thats the reason.

Thanks a lot, it worked!

Yes it is:

https://github.com/spesmilo/electrum/issues/2897#issuecomment-330535625

edit: glad it works for you now