SourceTec Sothink SWF decompiler

I used secureSWF to obfuscate a swf-file, and then opened it in Sothink and extracted the source code. Fine. I then once again obfuscated it (this time with a stronger setting). Now I want to re-open it in Sothink, but the old file won't go away. There is no close alternative, so I select it and pressed delete (again, in Sothink, not in any kind of file explorer). Not only did it disappear from the list, but it ALSO DELETED THE PHYSICAL .SWF FILE FROM MY DISK. fffffffff-----