Hi,
If I was you, I'd scan my System for Malware.:
Download, install, update and scan your System with the free version of Malwarebytes AntiMalware and if necessary do this in Safe Mode with Networking:
http://www.malwarebytes.org/products/malwarebytes\_free
"Advanced startup options (including safe mode)"
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And also Scan with the free version of SUPERAntiSpyware
http://www.superantispyware.com/download.html
SUPERAntiSpyware Free Edition is 100% Free and will detect and remove thousands of Spyware, Adware, Malware, Trojans, KeyLoggers, Dialers, Hi-Jackers, and Worms. SUPERAntiSpyware features many unique and powerful technologies and removes spyware threats that other applications fail to remove.
SUPERAntiSpyware Free Edition does not include real-time blocking or scheduled scanning.
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This is a very good Program to scan your System to remove Adware, etc:
http://www.bleepingcomputer.com/download/adwcleaner/
AdwCleaner is a program that searches for and deletes Adware, Toolbars, Potentially Unwanted Programs (PUP), and browser Hijackers from your computer. By using AdwCleaner you can easily remove many of these types of programs for a better user experience on your computer and while browsing the web.
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And just to be sure nothing is lurking in the background:
"TDSSKiller Rootkit Removal Utility Free Download"
http://usa.kaspersky.com/downloads/tdsskiller
Cheers.