how to uninstall zoosk messenger from windows 7?

Firstly make sure that nothing to do with Zoosk messenger is running in the background.
Also as Zoosk messenger is related to a dating site & it's available on a lot of peer to peer sites
or so I've read....
Do ctrl, alt & delete keys all at the same time to start task manager & see it zoosk messenger is showing in the applications of processes tabs. If so, End the Task.
Do an Offline Search, in Drive C....type in Zoosk, Click Search....If you find any folders/files,
Delete them. Empty your Recycle bin. REboot your computer and run an anti malware program
if you have one.
If you don't have one, you can Safely download malwarebytes here to run a scan of your computer:
http://www.filehippo.com/download_malwarebytes_anti_malware/
to get the malware out of your OS.

Merely be very careful of what you download due to malware, spyware, viruses, etc.
I did an extensive search in hopes this will help you in some way.

Firstly make sure that nothing to do with Zoosk messenger is running in the background.