malwarecide said:
Reformat your laptop , it might been compromised by a malware that controlled ur account ...
https://support.microsoft.com/en-us/kb/2623670
That is rather draconian. We don't know yet if it is malware and, if it is, there is a good chance it can be purged without resorting to formatting and reinstalling the OS, etc. In fact, formatting and reinstalling the OS may not work if the malware is lurking in the data or a software or driver installation file which would simply reintroduce it.