This is going to be very quick but I thought it would be better to post it as a diary rather than a comment.
I have just received an email purporting to be from the IRS which links to a page that attempts to download malware to your computer. It reads:
(Subject line:) Tax Payment N 46991709 is failed.
Dear Customers,
Your Federal Tax Payment ID: 31194211 has been rejected.
Return Reason Code C44 “ The identification number used in the Company Identification Field is not valid.
Please, check the information and refer to Code U 56 to get details about
your company payment in transaction contacts section:
[Fake link to http/eftps.gov/N**** removed]
Gil Kruse,
The Electronic Federal Tax Payment System
This is a very crude attempt to distribute a piece of malware to your PC -
Microsoft Security Essentials prevents it from being installed.
The sender (on my version) is from a hotmail address.
Hovering over the link will immediately show it is not to the eftps.gov site but to las-resturant.com.
This fake should be easily spotted by most spam filters but more sophisticated versions may get through. My general advice would be to only log onto sites using known links or previously used genuine ones supplied to you by your bank or the IRS.