Today I found 3 spam {and quite probably phishing) emails that contained no Sender Address; never seen that type of email before. After tracing through a few articles on the MS forums I found a suggestion to look at the actual header info for the email and see if there was a common denominator that could be used to set up a rule in my outlook inbox. Well it worked. The common denominator is that each of the spam emails has a "<>" at the end of the From: line; for example, "From: strengthen your back <>". The Rule is to look for specific words in the message header, then display a desktop alert and to delete it. No exceptions. The rule found and deleted the 3 spam emails from my inbox and dropped them into the deleted items folder.
The "From:" line is located just after the "Subject:" line in outlook. The method to open the email header is to double-click on the message and then select the Properties button - the Header info will be shown, in addition to any other info in the email; so please be careful and do NOT open or follow any hyperlinks in the original email or from the header info.
Not sure this is an universal solution but it worked on the 3 spams I received that all seemed to be associated with something called *.mail2world.com .