There is a new email going around that appears to be from Microsoft and is claiming to be an email account verification message. Per Microsoft, "Please be reminded that Microsoft will not send emails asking for personal information".
As per our usual advice, do not open attachments in emails that you aren't expecting or from people that you do not know. And, if you do know them, but it looks suspicious, check with them and make sure that they actually sent it before opening it.
The body of this particular message looks like this and has a PDF file attached.
MICROSOFT EMAIL ACCOUNT VERIFICATION SECURE MESSAG
Read your secure message by opening the pdf attachment. You will be prompted to open (view) the file or save (download) it to your computer. For best results, save the file first, then open it. If you have concerns about the validity of this message, please contact the sender directly. (firstname.lastname@example.org)
Thank You, Microsoft Windows Support