Cannot extract exported eclipse product (exported as archive)

I export 开发者_Python百科an eclipse RCP application (defined in a .product file) as an archive. But when I try to extract it using windows 7 build in extract tool I just get:

corrupted archive

I can extract the archive using 7zip though. Why can windows7 not open the archive created by eclipse?

Not sure, but I think I have seen this too.

Then it turned out to be an entry for the directory/folder that caused the trouble - i.e an entry on the form plugin/. The last slash was not accepted.