It's my first message and I'm crying...
I had about 3.5 bitcoin, I tried to use some a short while ago and got a message that there is a compulsory upgrade.
I downloaded and installed the upgrade on my iMac, restarted Electrum, and then it happened...
It immediately said there was not enough funds to transfer the amount of ALL my coins but continued trying to process it until it eventually said there is a zero balance.
BOOM! EVERYTHING IS GONE!!
:-(
^ No, do not click the popup message on the electrum wallet that said you need to upgrade your wallet to another version. By the way, what electrum wallet version you use? Because the latest update is 4.0.2
https://electrum.org/#download. You can directly check to the official website of the electrum.
Nevertheless, there is no way to return your bitcoin loss and sorry about that. Next time, be sure that you will learn from this mistake. Be vigilant of all times and don't be neglect.