There is very little chance of being able to contact the receiver. Cryptocurrency wallets are designed for user privacy and anonymity. And there is no Central authority to contact as would have been the case should this have been a fiat transaction.

Learning from the mistake moving forward and finding out the root cause, if it was a bug or malware to ensure it doesn't happen again.

Yes, transactions are irreversible and there's no way to take it back unless you know the receiver and he's too generous enough to send it back which I highly doubt he will do.

Sorry for your loss OP but it's either you have been a victim of;

• Phishing
• Malware

So it's more of a human error. You can also try to scan your PC for your sake.

Next time before sending to an address, verify and check it many times before pressing the send button.

Bitcoin transactions are final and irreversible, therefore always triple check before making a payment. If you are a victim of malware, you should be aware that using insecure OSes like Windows will lead you to money loss. If you were waiting for an excuse, now is the time you take Linux seriously.

Separate your tasks physically, the serious things like banking and money handling, should always be done in a safe environment, this can be achieved by booting a live Linux iso (such as Tails) or having an older dedicated computer for such tasks.

Securing windows is much harder than using Linux for mundane tasks such as web browsing banks and bitcoin handling. You could keep your windows cleaner by purchasing anti malware software which would in turn make it slower than it already is, but there is still a chance a new undiscovered malware infects you and steals your money anyway. Lower your chances of getting infected and switch to Linux today.

There's just no way that you could get that funds again mate. The blockchain is built this way. You should be careful next time in sending funds. Or probably some virus somehow got into your computer. If I were you, I would scan my whole computer and change passwords.

I agree with the others, and also agree that this should be a lesson, albeit expensive. Always double check the addresses you are sending to, and if possible use QR codes and perhaps even a hardware wallet for extra security. This is one of the downsides of blockchain technology - transactions are irreversible.

Did Electrum ask you for any updates when you tried to send your funds? If it did, then you have been a victim of the latest exploit in Electrum. https://steemit.com/bitcoin/@kingscrown/important-do-not-use-electrum-for-now-huge-exploit-found

There are some "infected" servers that force you to install a fake update of Electrum and when you try to send bitcoins, it captures your password and then they send bitcoins to their own Bitcoin address.  

Warnings have been posted everywhere, cannot believe you missed it.  

Are you sure that you are not infected? Usually, these things are hidden within your file systems and your operating system. Do a deep scan and try again. It is possible that your clipboard is messed up by the malware that you "thought" you send to the right address when in reality, you didn't, and the next thing is we're having a discussion about it. Or just like what Kakmakr said, you may have installed a fake update on Electrum, but the exploit has since been patched so that may be ruled out.

Funds are lost forever. That sucks, but yeah, a lesson with some price on it.

As far as I know many users have made such mistake, at least once. Usually they don't check the address which is a crucial mistake. Even if you copy it or scan through QR code you should check it. Since Bitcoin transactions are irreversible you can't get your money back unless someone from that wrong address returns Bitcoin to you. Which I doubt. So, learn from that mistake.

You have send the bitcoin to the wrong address, so it means that those bitcoins are lost and there is no way to recover them. This is one drawback of bitcoins and if it sent to wrong address we cannot get it back and also cannot claim it. It is our responsibility to check the address twice before sending Bitcoins to it.

Uh-oh. Be careful next time mate. The lost fund isnt comming back anymore and regarding to those comments above, it seems that you either have virus or you clicked some phishing link. Better clean up your drive now to avoid further missing bitcoins. Maybe he is still up to your funds.