Searching text within files

[thriii]

I have a plugin for photoshop that is not letting me continue with activation because it says my activation code is invalid. I'm trying to search for the text that the error msg provides so I can find the file thats stopping me from activating with the correct serial number. I've tried removing the plugin and all the files I know that it installed but still it doesnt work. So, how do I search for text/words that are inside of files so I can find this file? Or, is there a way to list ALL the files on my computer in spotlight? then I can figure out which file it is by the date created/modified on my computer

 

[GGJstudios]

Rather than Spotlight, why not search with Finder, which allows more search options? You can filter by type, dates, etc.