I checked alle downloads with an Electrum developer, all downloads are ok.
For the record: I am the Electrum developer who answered this user's emails, and we only checked his 3.0.5 download, because he claims to have deleted 3.0.3
yes right, but I checked in the browser download history, this was the right software from the correct website, there was no other Electrum 3.0.3, I am not stupid, I have never used a wrong download before. Also I checked my PC with an windows server administrator and a java/delphi programmer now. I have a 100% clean computer. I have used 6 different desktop wallets at this time, everyone is ok. But only this problem with Electrum. coincidence? stupidity? Sorry, but I do not believe in coincidences and I did not do anything wrong, quite the opposite. I am always careful, it is still a mystery to me and my friends. Fact is, now I was robbed by whoever and I used Electrum and nobody can help me.
Let me say first that I feel for your loss, and my advice to you is to get your bitcoins off of computers and onto either hardware wallet like Trezor or paper wallets.
It may interest you, I have just now been writing a fictional scenario where an intruder activates the camera on her target's PC, and simply reads the password the target enters and then reads the numbers on the 2FA authentication device. The intruder types the 2FA in quicker than he does, and locks him out.
Yes I made that up. It's fiction. Now I've publicly stated it, so maybe tomorrow the bad guy tries it out.
Do we know all the routes a bad guy might take? Nope, you cannot.