Thanks for all the updates guys.  A great effort by all - Teamwork always pays off! :)

John T
No rolling back, but you do want to uninstall the current driver if it's there but not working.
 
My steps, coming from Windows 7 were:
1/ uninstall driver
2/ upgrade to w10
3/ install driver as described at start of thread.

Wow, it totally worked! I'm impressed, you all saved me so much time and pain, so seriously, thanks for this! One last question, do I have to turn the signed-driver verification back on, or will it just turn back on when I restart? 

Hmm. I think it turns itself back on. I think those options only apply to the current session. But now you mention it, I'm not actually sure about that.

Tried installing my VS-100 on this computer as a test and during the install, I got to the point where you plug it in but it didn't do anything. I had to cancel out the install and it uninstalled it. Now when I try to install the driver again, I get this:
 

 
This is what I pasted in the code. I simply replaced the 700 with 100:

;---------------------------------------------------------------;
[Manufacturer]
%MfgName%=Roland,NTamd64.6.2,NTamd64.10
;[ControlFlags]
;ExcludeFromSelect=*
[Roland]
;; Windows7 - Windows XP 64
;; not supported
[Roland.NTamd64.10]
;; Windows8
%RDID0089DeviceDesc%=RDID0089Install, USB\VID_0582&PID_00FD ; VS-100
%RDID0090DeviceDesc%=RDID0090Install, USB\VID_0582&PID_00FE ; VS-100 M1
%RDID0091DeviceDesc%=RDID0091Install, USB\VID_0582&PID_00FF ; VS-100 M2
%RDID0089DeviceDesc2%=RDID0089Install, USB\VID_0582&PID_0100 ; VS-100
%RDID0091DeviceDesc2%=RDID0091Install, USB\VID_0582&PID_0101 ; VS-100 M2
[Roland.NTamd64.6.2]
;; not supported
;---------------------------------------------------------------;

I've not encountered that, so I don't know for sure, but I think you might need to uninstall the driver yourself, and then start from scratch.

Any idea where the driver is located?

TerraSin
Any idea where the driver is located?

I did an uninstall through the control panel (it was listed as VS-20 Driver or something like that). Then I downloaded fresh drivers through the support page and edited the RDIF1106 file (it'll be different for the VS-100 but should look similar), and made the changes that dustriplin suggested, then installed. 
 

TerraSin
Any idea where the driver is located?

If you mean for uninstalling, it should be visible in the "uninstall a program" link in Control Panel.

Without wishing to patronise anyone, I'm going to throw in a reminder of a point from earlier in the thread: if you don't know what we're all talking about here, in terms of drivers and INF files and driver signing and all the rest of it, this might not be a good thing to get bogged down in.

You can end up in a world of pain with this stuff very easily. I'm not saying you're not all smart, because I know you all are, and I'm not saying this is rocket science, because it's not. But do tread carefully. Certainly do not skim read the instructions in the opening post. Either follow them exactly, or don't do it at all, is my advice.

John TIf you mean for uninstalling, it should be visible in the "uninstall a program" link in Control Panel.

I meant the actual drivers. I'm going to have to manually remove them. I don't think that is what is causing the error though so I may be SOL on that one. Might just be the installer itself is buggered. I will give it another go tomorrow with a fresh copy.