Installation can not proceed

Question

When trying to install AirPort Express on my PC I get the message: "A later version of iTunes is already installed. The installation could not proceed."
What version should I use?

Answer 1

The following instructions are for configuring an Airport Express to “join” the existing wireless network created by a non-Apple brand of wireless router.
You have likely been directed to follow these instructions because you could not get the Airport Express working using the instructions provided by Apple. The instructions provided here will almost always work because (a) they require you to temporarily cable your Airport Express to your existing network so that you don’t need to mess around with changing wireless network connections on your PC or Mac during the configuration process and (b) they require you to remove all wireless security from your wireless router (since misconfigured wireless security protocols are the most common reason for configuration failures of an Airport Express).
Before starting, do two things on the Mac or PC you are going to be using to perform the configuration:
1. make sure you have installed at least Airport 4.1:
For Macs see http://www.apple.com/support/downloads/airport41formacosx.html
For Windows see http://www.apple.com/support/downloads/airport41forwindows.html
2. disable all network firewalls on the computer:
- Windows users should turn off the built in Windows XP firewall
- Windows and Mac users should disable (sometimes even uninstall) all third-party firewall or “internet protection” software they may have installed. Antivirus software is OK.
- Windows and Mac users that have installed VPN client software should disable or temporarily remove this software. Many VPN software clients install a firewall without telling you (Cisco’s is a common culprit).
Next - if you have been playing around with the Airport Express previously (perhaps messing up its default configuration), get it into a known state by doing a factory default reset of the device per:
http://docs.info.apple.com/article.html?artnum=108044
Next – access your wireless router’s configuration (usually done via a web browser on your Mac or PC) and do the following:
1. write down the SSID of your wireless router. A wireless router’s SSID happens to be the “name” it shows up under when you try to connect to its wireless network from a PC or Mac.
2. remove all wireless security protocols from the wireless router. Yes this is drastic – but it is only temporary. Remember you have been directed to these instructions because everything else you tried has failed, and the purpose of these instructions is to prove that you can get a bare-bones system up and running. Adding wireless security back in can always be done later – once you have proven that you can get a basic system going. Unless you really know what you are doing (in which case, your probably didn’t need these instructions in the first place) don’t attempt to “cut corners” by not following my advice to disable security. This means (a) do NOT disable SSID broadcast on your wireless router, (b) remove all MAC address filtering or MAC address based access control, and (c) turn off WEP or WPA security.