What is the extension

   .??

Some examples
http://en.wikipedia.org/wiki/List_of_archive_formats
Sounds like you need to update your app.
Cant say until I know the Extension used.
There is also a OS X operating system. if it is for that
system that is a linex base system and
OS X is usually compatible with Unix-like formats.

so ext please.

Lighthorse
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