Details? What OS, when do you get this, ...
Interestingly, I've had this exactly once - just after I read the original post.
For what its worth I am on XP SP3.
Actually I take that back. I get it every time I run <sqldev>\sqldeveloper.exe and the complaint is about <sqldev>\bin\sqldeveloperW.exe.
If I run <sqldev>\bin\sqldeveloper.exe (which is what I usually do) I don't get it.
Edited by: Jim Smith on Sep 14, 2009 1:39 PM
I am running windows XP, SP3
I think it's standard behavior for Win XP since SP2 - you also need NTFS to get it appearing.
I know this a very delayed answer to a 2009 question. But I had a similar problem today and tried to search for a reply and landed in this page. Later I figured out that the executable file was in blocked stage. Files received from mail and internet downloads are blocked based on security settings and execution will be permitted after review and allow manually. As a one time activity, the executable file can be unblocked (Right click - > Properties -> Click Unblock) after which this warning will not appear.