Now that Windows 8 has hit RTM there is a slightly newer version of Orca the MSI editing tool available. This one is version 5.0.9200.0, but when it’s installed, in the Programs and Features dialog it’ll show up as 8.59.25584.
To grab yourself a copy get the Windows SDK for Windows 8, install using the option to ‘download for installation on a separate computer‘, and make sure only ‘Windows Software Development Kit‘ is selected in the features list. You won’t be able to de-select the .NET 4 download.
After your download is complete you can either install Orca from the download directory, or collect up the files you need to keep a copy for use later on. The files you’ll need are listed here and are linked directly to Microsoft download location for ease of collection:
To install Orca just double-click on Orca-x86_en-us.msi and allow it to install. Job done!
I finally realised where to get hold of version 5 of Orca – the one most suitable for Windows 7 able to validate .msi files for Windows Installer 5. It was of course in the Windows SDK for Windows 7 and .NET Framework 4. Unfortunately there’s no mini-download for the msi sdk like with version 4.5, so for simplicity I’ve acquired the .msi for orca and put it online for download…
Orca 5.0.7693.0 (2.1MB)
If you would rather download the official version from Microsoft you need to install the debugging tools from the Windows SDK, then go in to Program Files\Windows SDK\7.1\Bin and orca.msi will be in there.
[Update 2012-09-08: there’s now a slightly newer version available here]
There’s a new version of Orca available (4.5.6001) that is suitable for Vista. You get it by downloading and installing the Windows Installer 4.5 SDK, available here (6.79 MB).
After the SDK is installed it will have delivered the installer for Orca into the program files folder (“%ProgramFiles%\Windows Installer 4.5\SDKTOOLS\orca.msi”). At this point you install it by double-clicking.
I recommend you archive the orca.msi file somewhere for the next time you need it.