Cant understand what happened.
And that is the problem.
If you don't understand what happened, you can't prevent it from happening again.
Actually it is pretty simple: You have downloaded and executed malware.
The interesting question is: Why did you do that? Did you believe some free-money-promise ?
Probably on some email from my business. I try to be very careful... but sometimes...
Possible. But my guess would be it was something from your free time.
I doubt a random malware you got through a business mail will create spam posts on bitcointalk..
You downloaded malware in your free time, didn't you?
