Please check the hash and PGP signatures of your Electrum wallet, also if possible upload your wallet installer and reply back with the link(asking because of this thread
https://bitcointalk.org/index.php?topic=1098340.0). Please answer the following:
Was this a cold storage wallet, and was it running on a windows machine completely unplugged from the internet?
Provide the exact link where you obtain the electrum wallet executable.
Do you have any remote softwares such as Teamviewer installed?
Where did you keep the Electrum seed, in a paper, saved on the computer, or in the cloud?