I am really amazed that no one from Adobe has answered this?
I have had exactly the same problem tonight and I think the error appears when
a FLA file that your corrupted FLA links library items from has been deleted.
Somehow the FLA still references to the old file it was created from.
For example: you have a file called ver_1.FLA, you do some changes, save it as
ver_2.FLA. All works fine until you delete ver_1.FLA, all of a sudden you will
get error messages opening ver_2.FLA.
I am sure there must be some directory that need to be flushed to reset the
library references?
Stefan
it sounds like you should delete it and then put it back