Sparktrust Removal

The short approach could be to try the below to tools:

Now please download Junkware Removal Tool to your desktop.

• Shut down your protection software now to avoid potential conflicts.
• Run the tool by double-clicking it. If you are using Windows Vista or Seven, right-mouse click it and select Run as Administrator.
• The tool will open and start scanning your system.
• Note: That JRT may reset your home page to a google default so you will need to restore your home page setting if this happens.
• Please be patient as this can take a while to complete depending on your system's specifications.
• On completion, a log (JRT.txt) is saved to your desktop and will automatically open.
• Attach JRT.txt to your next message.

Please download AdwCleaner by Xplode and save to your Desktop.

• Double click on AdwCleaner.exe to run the tool.
  Vista/Windows 7/8 users right-click and select Run As Administrator
• Click on the Scan button.
• AdwCleaner will begin...be patient as the scan may take some time to complete.
• After the scan has finished, click on the Report button...a logfile (AdwCleaner[R#].txt) will open in Notepad for review (where the largest value of # represents the most recent report).
• The contents of the log file may be confusing. Unless you see a program name that you know should not be removed, don't worry about it. If you see an entry you want to keep, let me know about it.
• Attach the logfile to your next next reply.
• A copy of all logfiles are saved in the C:\AdwCleaner folder which was created when running the tool.

Additionally you can look at the log from AdwCleaner for anything related to Sparktrust and delete it.

It the above do not help then you need to work thru the below:

READ & RUN ME FIRST. Malware Removal Guide

and attach the requested logs when you finish these instructions.