folks, I have the same problem. a months unable to alive arduino on my home comp. think problem is Win8.1 and driver. yesterday uploaded new driver 1.6.0, and first success. part. I am now testing 3 MEGA boards, 2 USB cables. problem is in COM ports, the same report. one board is running. on bottom status line is Arduino ... on COM4, Tools/Port says COM4, WIndows says Arduino on COM4. this one is working. Unplug and plug next MEGA : bottom status line : Arduino ...on COM4, Tools/Port says COM5, WIndows Arduino COM5. : can't open device "\.\COM4":
Unplug and plug next MEGA, result : bottom status line : Arduino ...on COM4, Tools/Port says COM3, WIndows Arduino COM3. : can't open device "\.\COM4":
switch off and on software, switch off and on windows don´t help, the same result.
how to match bottom status line and Tools/Port report?