I'm no computer expert so I may be going into conspiratard territory here (help me out if so). But the whole Alfa Bank / Trump Tower server thing sure seems like a pretty big coincidence at this point, doesn't it?
You may remember this NYTimes
article from late October that said the "F.B.I. ultimately concluded that there could be an innocuous explanation, like a marketing email or spam, for the computer contacts."
But I think it's interesting to note that:
(a) this does not mean the FBI concluded it WAS innocuous, only that it "could be"
(b) the article acknowledges the FBI "spent weeks" investigating the server and briefed congressional leaders about it
(c) at the time of the NYT article, the sources thought Russia wasn't trying to get Trump elected, which we now know is wrong... so they may have also underestimated the nefariousness of the server