VirtualAcorn Technical support:
Running VirtualAcorn Products on Windows 7

VirtualRPC doesn't run

Due to the design of Windows 7 not all errors generated by applications are shown on screen. It's possible therefore that VirtualRPC is producing an error message but that Windows is hiding this message from the user. All details of error messages are held in the Windows 7 Event Viewer. If the suggestions on this page do not resolve your problem when you will need to use the Event Viewer (located in the Control Panel) to find out what error message VirtualRPC is generating. There are a number of good articles available on-line that cover using the Event Viewer.

This article covers two eventualities:

• Running VirtualRPC produces an error message
• Running VirtualRPC makes the timer spin for a few seconds then nothing happens

Sound System

Before looking at more complex reasons why VirtualRPC won't run the first and easiest test is to ensure that you can play a sound on your PC and hear the sound through your speakers. If you have a desktop PC, where the speakers are not plugged in, then VirtualRPC will not work. This problem is far less likely to occur on a laptop, but it can happen. Before testing anything else make sure your computers's sound system is working.

ntdll.dll

On a small number of machines running Windows 7 double clicking on your VirtualRPC icon to run it can cause an error message, or no message and a briefly spinning timer. There can be several possible causes for this, however the most common is related to ntdll.dll. This article is not the space for a technical description of this problem, luckily solving it is very easy:

• Firstly right click on your VirtualRPC Shortcut on the Windows desktop.
• Then click on Properties from the Windows menu which opens.
• The VirtualRPC application Properties window will open.
• Click on the Compatibility tab.
• The following window will open.

• Click on the Run this Program in compatibility mode for: button.
• Choose Windows 98 / Windows Me from the list.
• Click on the Run this program as an administrator button
• Click on Apply then on OK.

Now run VirtualRPC in the normal way. The product registration window should now open and you will then be able to request an unlock code.

Once you have entered your unlock code and clicked on the VirtualAcorn Unlock button you will need to go through the Licence Agreement and depending on your version of VirtualRPC the Select Model window. At this point VirtualRPC will start to initialise RISC OS. With the Compatibility Mode enabled RISC OS will operated very slowly. Don't worry about this. Wait until RISC OS has entered the desktop and the hourglass vanishes, this may take several minutes. Once the entire RISC OS desktop has appeared simply click on the close icon for the VirtualRPC window using the White Mouse Pointer. Now you need to disable the Compatibility mode:

• Firstly right click on your VirtualRPC Shortcut on the Windows desktop.
• Then click on Properties from the Windows menu which opens.
• The VirtualRPC application Properties window will open.
• Click on the Compatibility tab.
• Untick the Run this Program in compatibility mode for: button.
• Click on Apply then on OK.

Now when you run VirtualRPC you will find that it behaves normally and the problem will not re-appear.