VirtualAcorn Technical support:
Disabling User Account Control on Windows Vista
Before unlocking a VirtualRPC on Windows Vista
Disable User Account Control
User Account Control (UAC) must be disabled in Windows Vista before unlocking and running a VirtualRPC. Without User Account Control being disabled a number of rather nasty things can happen. You might find that changes made to the RISC OS !Boot system will vanish, documents that have been altered lose their changes. You may even find that Windows "interrupts" VirtualRPC in the middle of your work.
Luckily disabling User Account Control is very easy.
Firstly open the Windows Control Panel. In the search options dialogue (top right) type UAC and click on the Search button.
The top result returned by the search will be Turn User Account Control (UAC) on or off. Click on this link and the User Account Control dialogue box will open. Untick the Use User Account Control (UAC) to help protect your computer option and then click on OK.
You should now shutdown and re-start your computer. This should stop the "virtual" files, produced by User Account Control, being presented as the real files. You should keep User Account Control disabled from this point onwards.
Technical explanation
User Account Control is a rather nasty "feature" in Vista. To explain in brief what happens is that when you (or an application) look at files on a disc (normally in program files) you don't actually see the files that are there, but a local copy of them that is unique to your user account. This may not make sense so it's worth me providing an example.
The first thing you will need to do is to turn on the Show hidden files and folders option from the Windows Control Panel. To do this open the Control Panel from the Windows Start Menu. Make sure the Control Panel is running using the Classic View. Now double click on the Folder Options icon. When the window opens click on the View tab and then tick the Show hidden files and folders option. Now click on OK.
Now open the Computer window from the Start menu and open your harddisc. Go into your user account and you will find an Appdata folder. Go into this and you will find a Local folder, inside this is a final folder called VirtualStore. In here you will find a copy of your Program Files folder. If you navigate down you will find a copy of VirtualAcorn. This will not be a complete copy but will contains copies of the files you have altered.
So what's this all mean? Well when you alter a file inside VirtualAcorn the file itself isn't changed. What happens instead is that a copy is made inside the VirtualStore inside your user account. The version of the file inside VirtualStore is presented to you as though it was the real file inside Program Files. Suppose you change a file and someone else logs onto the machine under a different account. If they then go and look at the file you changed they find that the changes have vanished. This is because Vista is showing them the original, not the altered copy from your VirtualStrore. I can't see the end of the chaos this could cause for users of all sorts of program, luckily this "feature" can be turned off.
