First and foremost, ensure that you have subscribed to one of your wireless carrier's data services plans and that your carrier has activated your plan for you. Without enabled data services, you will not be able to browse the web, use messenger applications or retrieve email. Secondly, the Treo communicator relies on an ISP to establish a data connection so customers need to have the dial-up number handy to set-up network preferences. In some cases, your wireless carrier provides those ISP services. The Handspring CD that comes with the Treo communicator includes a data installation wizard that guides you through the process of setting up user names, passwords, domain names, etc. Once these are set, you will be able to take advantage of wireless data applications.

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