I have a repeatable problem with my laptop (an HP G4 250 that came with windows 10). I can be happily on the Internet, but opening Spyder causes the Internet to immediately die. Now, the system does something rather unusual. I am not disconnected from the router, and the wireless icon still says I am connected and have Internet access. But streams crash, webpages refuse to load and say there is no internet connection, and I can;t even access my router's config page. 
Closing Spyder fixes the problem. Not instantly, but when Spyder is open, it creates several pythonw.exe network requests (seen from resource manager) and the Internet is restored when those processes close themselves upon exiting Spyder (typically 10 seconds to 2 minutes, depending on system load). 
I have added Spyder to my firewall, but that has done nothing. I haven't added (nor found) pythonw.exe, but it's not Spyder that has the problem with connecting, it's my entire machine. 
It's not coincidental. It's happened now, 2 days in a row, and is highly repeatable. After a while with Spyder being open, I can sometimes receive intermittent Internet function, but it frequently drops until I close the program. 
After experiencing it last night, I purged my driver and reinstalled it fresh, and that has fixed nothing. I am running the latest wireless driver provided by HP for my machine. As this problem only occurs when running Spyder, I doubt it's a driver or hardware issue.
Any ideas?
I had the same problem when Spyder was open, with all of my Internet browsers, on both Windows 7 and Windows 10. The newest update of Spyder has fixed most of this for me. Try opening up the command prompt and typing:
conda update spyder.
Hope this helps!
Anaconda 3 Spyder appears to be causing internet outages on Windows 10