a number of different file types...
http://filext.com/file-extension/APF
http://file-extension.net/seeker/file_extension_apf
http://www.file-extensions.org/apf-file-extension
http://www.dotwhat.net/lang_eng/files_other/extension_apf/id_2771/
http://filext.com/alphalist.php?extstart=^A
Do you know what the source application was that produced this file you have? Where did the file come from?
And I want to know what program(s) uses an .apf format? It seems to be a graphic program of some sort.

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