I have seen that when I change a project to use Flex 4 sdk in Flex builder 3 the html wrapper files are deleted and not regenerated.
I wonder if this is a common behaviour or if it's something going wrong here.
(the generate wrapper file option is enabled of course)
thanks in advance.
In Flex 4 we changed our HTML wrapper to use SWFObject, FB3 probably doesn't know the right files to copy.
Following your observation I have copied the folders:
from Flex sdk 3.3 to Flex sdk 4 and that solved the issue.
Thanks a lot for your help.