Another debug launch and target program/erase failure......
hmmm.. ignore that last post. I have been an idiot......... 
The clean install on the laptop DOES work! It helped when I plugged the target into the laptop rather than my main pc!
So, all I need to do is getting it working on my development PC.
Both have clean installs as of today (both checked for updates).
Laptop (that works) is windows 10 x64. target appears as a “ST-Link Debug” with 3 driver files listed:
c:\WINDOWS\system32\DRIVERS\winusb.sys (v 10.0.10586.0)
c:\WINDOWS\system32\WdfCoInstaller-1009.dll (v1.9.7600.16385)
c:\WINDOWS\system32\WinUSBCoinstaller2.dll (v6.1.7600.16385)
PC (that does not work) in windows 7 x64. target appears as “STMicroelectronics STLink Dongle” with 3 driver files listed:
c:\WINDOWS\system32\DRIVERS\winusb.sys (v 6.1.7601.17514)
c:\WINDOWS\system32\WdfCoInstaller-1009.dll (v1.9.7600.16385)
c:\WINDOWS\system32\WinUSBCoinstaller2.dll (v6.1.7600.16385)
So the obvious difference is the winusb driver version but they both came from windows update and I think they are different due to the different versoins of windows. (am I correct?)
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