You may have spyware/malware/scumware installed on your system.
Perform the following:
Please post back here and let us know if this has cleared the issue up.
Perform the following:
- Disable System Restore - Right Click on "My Computer" --> Choose "System Restore" and check "Turn Off System Restore On All Drives"
- Perform an online virus scan here
Download, update, and run these tools:
- Spybot Search & Destroy here
- Lavasoft Adaware here
- CWShredder here
Please post back here and let us know if this has cleared the issue up.