Addit! Pro For Flight Simulator 2002

I see a dialog that says, "The feature you are trying to use is on a network resource that is unavailable" or "Error 1706. No valid source could be found for product Addit! Pro For Flight Simulator 2002". What should I do?

NOTE: Substitute 2002 for 2004 in all places below.

If a critical part of Addit! Pro is missing or corrupt or if you pick the "Repair Addit! Pro For Flight Simulator 2004" option, the Windows Installer looks for a file called apfs2004.msi. This msi file is a Microsoft Windows Installer data file and it works much like a zip file in that it contains other files needed by Windows Installer. If apfs2004.msi cannot be located, Windows Installer raises this error:

The feature you are trying to use is on a network resource that is unavailable.

Click OK to try again, or enter an alternate path to a folder containing the installation package 'apfs2004.msi' in the box below.

Use feature from:
D:\Documents and Settings\[Your Windows Account Name]\Local Settings\Temp\install\

Follow these steps to make apfs2004.msi available to Windows Installer so it can complete successfully:

1. Download the latest version of Addit! Pro For Flight Simulator 2004 from http://www.byteforge.com/products/ap_fs2004/download/index.htm.
2. Extract the file apfs2004.msi from the zip file you downloaded in step #1.
3. Place apfs2004.msi in the folder mentioned by the Windows Installer (for example, "D:\Documents and Settings\[Your Windows Account Name]\Local Settings\Temp\install\".

Now try again. Windows Installer will locate the file and update Addit! Pro automatically.