Make sure that your Windows box3n are up-to-date on their patches. There's a flaw that's been fixed by an MS patch on the SMBus that's been seeing increased port scanning activity. Would-be hackers are targeting the affected port 445, & if your box is open on that port & not patched, you could be in for a long week next week.

"A recent surge in port 445 scanning activity could herald impending hack attacks, and industry experts have warned firms to take immediate steps to ensure that the affected Windows ports are secure."