As with any email, if you don't recognize who it came from, do not open it. And even if you do recognize the person it came from get in touch with that person and ask if they sent you an email. I for one don't trust any emails, inbox spam or otherwise. If I don't know them...delete delete delete.
BTW: When I was a newbie (long time ago) I opened one and BAM! My laptop went bonkers.