You might be aware that a new version of Flash Builder 4.6 was recently released. Along with that release, Adobe also released Flex SDK 4.6. Unfortunately, Flash Catalyst projects are not compatible with the new SDK.
Flash Catalyst Project error in Flash Builder 4.6
The reason for this error is that Flash Builder 4.6 does not come with Flex SDK 4.5 installed. You can manually install this SDK, and you should not have any issues.
If you would like to convert your project to use Flex SDK 4.6, there are a few steps you need to perform. The first is to disable the Automatic Check Compatibility function. Note: You can not do this in the Project Properties panel, it must be done via the menu.
Flash Catalyst Compatibility Checking
With the Flash Catalyst Checking disabled, bring up the Project Properties panel.
Project Flex SDK Properties
Change the SDK version to 4.6 from 4.5. Click OK. Your project will now compile under the new SDK. However, this means you will no longer be able to round-trip the project with Flash Catalyst.
Hope this quick post helps.
So if you switch the dropdown to 4.5, you can use Catalyst?
By: Brent Hathaway (@brenthathaway) on February 17, 2012
at 1:26 pm
Correct, assuming you have manually installed the Flex 4.5 SDK in your Flash Builder 4.6 install.
By: Chris Griffith on February 17, 2012
at 1:46 pm