Answer:

ADWARE

Answer	Crossword Clue
ADWARE	Relative of spam
ADWARE	Pop-up generators
ADWARE	Producer of pop-ups

ADWARE	Program that generates online pop-ups
ADWARE	Program producing pop-ups
ADWARE	Online pop-up source
ADWARE	Pop-up producer
ADWARE	Invasive apps
ADWARE	Producer of Web pop-ups
ADWARE	Pop-up-producing program
ADWARE	Programming behind computer pop-ups

ADWARE	Norton AntiVirus target
ADWARE	Program producing online pop-ups
ADWARE	Invasive software, perhaps
ADWARE	Program with popups, perhaps
ADWARE	Hard-drive infestation
ADWARE	Programs with popups, perhaps
ADWARE	Pop-up generator
ADWARE	Source of some pop-ups

ADWARE	It can dirty your Windows
ADWARE	Program with plugs