Microsoft has confirmed that the October update has broken Windows media player. Users will note that they're unable to seek in some file types, an essential part of the app.
On top of that, there are issues with default file types. Some users are unable to set win32 program defaults with certain apps using ‘Open with'. Some default win32 programs, including Microsoft Notepad, are also unable to set as default.
Microsoft reports that in some cases, simply trying again will fix the issue. For others, it's working on a fix that will be coming in ‘late November', so sometime this week. The fix for the media player issues is yet to get a release date.
Committed to Quality
At the end of the day, these aren't the major bugs we've seen in the past. However, they do add insult to injury considering the huge delay in the October update's re-release. At this point, user's best bet is to wait until several months after an update's release to avoid any issues.
The silver lining here is that Microsoft is getting better at communicating about Windows 10 update issues as it promised. We're yet to see the other half of that promise, fewer issues, but that's unlikely to come until the next update.