It would be worthwhile if you mentioned what OS you are developing on: Windows, or Mac OSX?
In general, you'll be asking Flex Builder to deploy your build to a web-accessible location provided already by the IIS web server (if on Windows), or the Apache web server (if on OSX.) Here's how:
- choose Properties on your Flex project
- select Flex Build Path in the left panel
- change the Output folder for your project.
On Windows, you'll typically choose an output folder such as C:\inetpub\wwwroot\xyz ... where xyz is the name for a folder you created to hold your project's output files. That will be accessible as http://localhost/xyz/YourFlexApp.html
On Mac OSX, a good output folder to use is /Users/yourusername/Sites/xyz ... where yourusername is your user name, and xyz is the name for a folder you created to hold your project's output files. That will be accessible as http://localhost/~yourusername/xyz/YourFlexApp.html
Important: Ensure your local web server is installed and enabled.
Additionally, you'll want to change your Run/Debug settings so that Flex Builder launches your project via http:// URL instead of via a file reference. Here's how:
- choose Properties on your Flex project
- select Run/Debug Settings in the left panel
- select your application in the main list
- click the Edit button
- under URL or path to launch, uncheck Use defaults
- change the Debug, Profile, and Run URLs to point to your web-accessible location.
I hope this helps.