What's new in v3.17:
*) fixed sudden disconnects from router (introduced in v3.15);
If you experience version related issues, then please report them to support@mikrotik.com.
Winbox is available here:
http://www.mikrotik.com/download
If you try to upgrade directly from Winbox loader and version is not available, then you might need to wait for a while until cache in path between your device and our servers is refreshed.