You can use grep for windows (in that answer there are several download options - https://superuser.com/a/301075/321990).
An example command that will match (it will search for a regex match recursively from where it's executed):
grep -r -E ".+\@.+\..+" *
The file matched contains this:
It will print you the 3 email lines, near the file name. It will look like this:
Where yo.txt is the file containing the strings above, and located under 'new' folder
If you only want the filenames, you can add the
-l parameter to grep:
grep -l -r -E ".+\@.+\..+" *
And it will only print:
The regular expression I've used is very simple, and likely to find more things, cause it's not accurate. You can search the web for a better regular expression to check email addresses, and change
".+\@.+\..+" with what you've found.
Hope it helps!