Block it for now. you need to note the exact message to get it right. Have you checked for virus in particular the "blaster worm"
If everything works when you block it then you can assume it is nothing to worry about. It may be that something you done whilst surfing has made this happen for example if you try to copy a webpage using word the firewall may ask you if word can access the internet. Sometimes printer a page can trigger "spooler " messages.