If you have updated to Flex 3.5 you want to be sure to grab the new version of the SDK. There is a bug that has been fixed which caused issues with the auto-update UI. Here’s the scoop.
The Flex team has released an update to the 3.5 SDK that addresses an issue with the Flex-based AIR auto-update UI packaged within the SDK (SDK-24766). The refreshed build, SDK 3.5a, has only a few files modified in order to fix this issue and this change does not affect the signing and caching of the SDK 3.5 RSLs originally released in December.
We encourage all developers using SDK 3.5 to upgrade their build to SDK 3.5a to continue their development. The SDK 3.5a can be found in the “Latest Milestone Release Build” table here:http://opensource.adobe.com/wiki/display/flexsdk/Download+Flex+3.