Looks like malware to me. I'm sure you don't want that on your computer
Use Google to search for not-a-virus adware win 32 agent zk & see what comes up.
Did you scan the files with your AV before opening them? Heaps of files are infected, so you should always make sure that you're using a good AV program. Keep it updated & scan all downloaded files before opening them.
If you're infected, I suggest you go to a site which specialises in malware removal...there are links to some sites below. Some AVs may get rid of this for you but we're not malware removal specialists, so IMO you're better off going to those who are
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