List files that do not match the search pattern

I need to list the files that do not match the search pattern:

Example:
cat file1
This is how it should work

cat file2
This is why I like Unix

grep -option? Unix * (or some other command)
returns file1

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I will close the duplicate thread.

I by ,istake submitted the thread under wrong forum and had no idea how to change the forum without creating a new thread.

man grep

grep -vl Unix *

I have used this command but it doesn't work

can you elaborate on the "it doesn't work" part, pls?

grep -c Unix * | nawk -F: '!$NF {print $1}'

It works pretty good..

Thanks