How To Transfer Coins From Bitcoin Core to Electrum to avoid Sync Process?

Question

I am super new to bitcoin and to be honest am not sure what I'm doing. I needed to buy something via bitcoin, and its recommendation was to download Bitcoin Core Wallet, so I did that and bought bitcoin to the receiving address on there, however I didn't know how much space was needed. So now I have sent the money to my Bitcoin Core address, but the wallet is trying to sync (and its taking forever which apparently is normal) and I'm not even sure my computer has enough space for it all. I read that I should try to transfer it over to Electrum, so I have that downloaded. I tried doing the Sweep Keys thing, but every time I try it, it says "no inputs found (note that input needs to be confirmed)"

Can anybody give me a hand here? I unfortunately will need pretty specific instructions.. Thanks :)

Answer 1

To relieve your space problem, You could either run it on an external drive, or run Bitcoin Core under prune mode. Depending on your OS, you'd need to find a file called bitcoin.conf, modify that, and restart your Bitcoin Core Wallet process. The file would look something like this

The line for prune mode reads

# Enable pruning to reduce storage requirements by deleting old blocks. 
# This mode is incompatible with -txindex and -rescan.
# 0 = default (no pruning).
# 1 = allows manual pruning via RPC.
# >=550 = target to stay under in MiB. 
prune=550 <- change this number if needed

Electrum is a light-weight wallet that relied on trusted nodes for transaction information. This page explains the steps needed to migrate from Bitcoin core to Electrum. According to that, you'd need to dump your private key from Bitcoin core and sweep that into Electrum.