If you use the car-v3-alpha11 firmware it is possible to use the Empeg as a Rio receiver, at least so they say. However, in order to do so you also need software on the server side (where all mp3's are). In the old days you could use various kinds of server software, including the original Rio one.
All good and fine, however I am running Windows 8.1 on my 64 bit computer and the original software does not install since it contains some 16 bit code. And I can not find any other Windows based server software for the Rio receiver.

My question: I would like to install some server software to use the Empeg mkIIa as a Rio receiver on Windows 8.1 64 bit. Does anybody know where I can find software that I can use for that?

Install a virtual machine to run an operating system that does work with the Rio server.

It's likely that it's merely the installer that contains 16-bit code. Install it in a Windows XP VM and then copy the files out?

Did not think about the VM solution, thanks. Will give that a shot.
And it may well be the case that only the installer is 16 bit, I will have a look in the VM.

Original software v 1.04 installed just fine on my windows 8.1 64bit.

Strange, I consistently get an error 'Setup failed to run installation: Kan RPC niet uitvoeren'. The second part is in dutch, is Windows related and means 'can not exucute RPC'. At that moment the installer tries to execute a program called inst16.exe which, when executed on itself, generates an error that it is not 64 bit compatibel.
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I am running the installer in XP compability mode and enabled/started the RPC services to no avail. Am I doing something wrong?