I've just updated my one-year-old 64-bit (Gigabyte board / Intel i5 processor) Windows 10 system with the Anniversary Update. Everything seems to work OK (fortunately) apart from the Sleep Mode. I have an SSD for the Windows system disk / programs and a HDD for data storage.

Previously, if you put the system in Sleep mode, everything stopped (screen, mouse scanning light, system fans etc.) and came back to life when you moved the mouse or lightly touched the power on button. Now everything stops apart from the fans, which stay 'whirring' as normal. However, when you try to wake the system up (By moving the mouse or touching the power button), the PC doesn't respond. The only way to get it going again is to switch it off entirely and re-start it.
Oddly enough, Hibernate works as it should do; mouse movement restarts the system, apart from the fact that occasionally PC jumps back into life itself.

Anyone any ideas how I fix this annoying bug - or how I report it to Microsoft? Thanks.