|They should not be added again automatically. The answer is not reverse engineering but is to eliminate the malware that keeps putting the lines back again.|
Run these three freebies for starters, in the order given. They often unearth what your anit-virus program can miss:
(blue "Download Now" button on right).
Download and "Save" the file somewhere. Go to the saved file then double click it to run the program. Use the "Scan" button, followed by the "Clean" button.
Junkware Removal Tool (JRT)
(blue Download button).
Download and "Save" the file somewhere. Go to the saved file then double click it to run JRT. It might appear to have stopped at times or flash the screen but sit tight until it has finished.
(use the "download" button rather than the "buy" button).
Install and Run the program but before running the Scan go to "Settings > Detection and Protection" and put a checkmark in "Scan for rootkits". Quarantine anything it finds.
Please copy/paste the logs on here so that we can see what is going on.
Always pop back and let us know the outcome - thanks