Start the machine in safe mode or using Last Known Good Configuration; click here . Disconnect your machine from the internet.
On another PC, download malwarebytes antimalware ( click here ) and latest definitions ( click here ) - copy the files onto your PC, run the installer but choose not run the program immediately. Run the mbam-rules.exe file to update the definitions. Then run a full scan with antimalware. YOu can download Superantispyware and its definitions too if you'd like to scan with both. File; click here
Definitions; click here