System Workbench for STM32

I had the same problems.

My solution was somewhat like your.

To get it to work I first tested to remove all on PATH with:
set PATH=

When I tried to start eclipse it complained that it was missing java so the solution that worked for me was a bit-file with:

set PATH=C:\ProgramData\Oracle\Java\javapath
C:\Ac6\SystemWorkbench\eclipse.exe

This post is just to give others more info on what to do...
I'm using
W7-64bit.
Eclipse Luna Service Release 2 (4.4.2)
System Workbench for STM32 - C/C++ Embedded Development Tools for MCU, Version: 1.7.0.201602121829
System Workbench for STM32 - GNU Tools ARM Embedded (for Windows 32bits), Version: 1.7.0.201602121829