You can add $1 billion for the discontinued in 48 days https://en.wikipedia.org/wiki/Microsoft_Kin Kin social networking phone, in which they also scored an own goal against their cloud offerings by trashing the database running their purchased userbase: https://en.wikipedia.org/wiki/Microsoft_data_loss_2009
The total losses, official or not, have got to run into the tens of millions.
Which was part of why the Kin was so late, they moved every Danger employee they retained who was working on the Hiptop line to the Kin, then had to pull a bunch back to finish 2 more versions. Who could have guessed that Deutsche Telekom could pose a serious threat to Microsoft?
The Zune came out in November 2006 - less than three months before the iPhone was introduced and a little bit over a year before iPod sales started declining.
Unlike today, where we have multiple Surface-branded products, back then Microsoft only had Xbox, which operated as an entirely separate division from Windows + Office.
Before the Zune, MS tried to be the software partner for non-iPod devices, with the Windows Media Player store and Plays4Sure DRM standard (which they botched). It's only after it all failed that they rushed into the market with the Zune, which was a partially redesigned rebrand of a Toshiba MP3 player that was in the works.
Microsoft introduced a hard drive based player years after the flash based Nanos were already more popular.
Then MS released the flash based non touch screen Zunes after the iPod Touch was becoming popular.
Finally they released the touch screen Zunes after the App Store came out and the Zunes couldn’t run third party apps. Even the hard drive based iPods had a few curated third party apps by 2005.
But for the rest, I doubt MS would have succeeded in those markets even under the best of circumstances. The iPod made Apple big again, but without Steve Jobs as the pitchman, it wouldn't have had the massive impact it did. The offerings of MS (the Zune) and others (Creative, Sandisk, Toshiba, Sony, etc.) were more than good enough, and they worked with a variety of online music stores. It's just without the brand cachet of the iPod and Apple's lifestyle marketing, it's hard to get excited about an MP3 player.
Slack and Dropbox are both huge inside startups, but nonexistent in old-school enterprise companies. Nobody at work wants yet another login to have to remember. I know this because I work inside a digital team at a 3000-person company where everyone swears by O365's out of the box capabilities. Skype for Business and OneDrive for Business inside of an O365 plan is "good enough" for a lot of people.
Dropbox has made losses each year since 2015. It's great that it's achieved good market share since it started in 2007, but maybe there's a limited enterprise market for something that's a one-trick pony. And one-trick ponies are the polar opposite of MS' strategy.