How to open Apple AppleDouble resource data .appledouble files
Have you had trouble opening the appledouble file on your computer? What are appledouble files? We explain what they are and recommend software that we know will open them.
What is appledouble file?
An appledouble file extension is related to AppleDouble file system introduced in Apple A/UX system.
Apple AppleDouble resource data description
The appledouble file extension is associated with the AppleDouble file format introduced with the first Apple Unix operating system called A/UX.
AppleDouble is similar to AppleSingle file format. However AppleSingle contains resources and data in one single file and AppleDouble in two separate files.
AppleDouble resources part with Finder meta-data has .appledouble file extension and data part is stored in original file format with original file extension. AppleDouble format is better for transport data through Internet, because non-Mac users can open the original file without other decoding like AppleSingle format.
AppleDouble file format is still supported by the Mac OS X. It is used to store Finder meta-data on drives with file systems that don't support resource forks, such as NFS and WebDAV.
Mime types:
multipart/appledouble
Suggested software to open appledouble file

macOS
A Unix-based desktop operating system for Apple Mac computers

Mac OS X
Unix-based operating system for Apple Mac computers