I called Support and Was told that they are aware of the issue and that are working on a fix.
No Estimated Time for the Fix.
But They also told me to uninstall the most recent Windows updates and that would correct the issue using Windows 10
So I uninstalled the most recent Windows Security Update 3/15/2017 and and the Adobe Flash update and now I can view my Slingbox
Microsoft released an update today to fix the update they broke on the 15th, which in turn cause the "Slingplayer for Web" to fail. Either wait for it to install automatically, or go to Updates in Settings, and click the "Check for updates" button to download the fix. I wrote about it here: https://community.slingbox.com/message/202393#202393
I had the same problem on my Windows 10 laptop and disabling fast startup resolved my case. Fast startup bypasses some device initialization and that may be the cause. You can try it with the following steps:
- Control Panel - Power Options
- Click on Choose what the power buttons do
- Click on Change settings that are currently unavailable
- Uncheck Turn on fast startup box
- Restart WIndows 10
- Launch Slingplayer for Windows