I had a previous version of electrum and did a transaction. Same wallet is installed on two devices. Now the wallet dose not sync plus one of the addresses is empty( ON both devices it is not syncing). When i check all addresses in the blockchain they have their required balances but one address has been cleaned out. And no I did not download from a suspicious site a new electrum wallet. But Did so from the official website. And If I had downloaded from a suspicious site my wallet would have been empty now. But ONLY one address has been cleaned out.
Have you actually verified the digital signatures of the wallet installer files? If you haven't, then you cannot be sure you did not download a malware version of the wallet... there are literally scores of posts in the Electrum from users who swear that they "downloaded only official Electrum" from "official website"... and then say they are running "latest version 4.0.0"
I fail to understand how that can happen.
Without knowing the specifics, it could be one of several reasons:
- Hacker just took the largest amount, couldn't be bothered with your dust
- Your wallet wasn't created from a seed, and is a collection of individual private keys and only one of them has been compromised
- The coins in that address were simply used in a transaction that you forgot about, so were spent by you, but that transaction doesn't show up in your wallet because it won't sync
I'd recommend:
1. Verify the digital signatures of your Electrum installer
2. Try manually switching servers in Electrum until you find one you can connect to and sync your wallet... until it's synced properly, it will probably be very difficult to figure out what exactly has happened.