I don't think is hidden partition. I booted the PC with the old hard drive and the disk management could see all the drives. While it was working i ran 2 antivirus and Microsoft Windows Malicious Software Removal Tool. The removal tool found something and removed it but it didn't fix the problem. And now when I search for something on google the links sometimes send me to http://maybeask.info/search.php and other sites I didn't want. I think its time to reinstall windows.