I have been into the same problem a few hours ago, but this is how i have been able to resolve it.
Download ADB from this Link: http://adbshell.com/downloads
Choose out this option:
ADB Kits (525 KB)(adb.exe AdbWinApi.dll AdbWinUsbApi.dll)
Extract all the 3 files you have downloaded from the extract.
Then paste the 3files in your SDK=>platform-tools folder.
I that exactly worked for me.
All the best.
