SIT is the archive format that is especially at home on the Apple platform. SIT is a commercial format of the software Stuffit for archiving and compressing data. The format comes originally from the Apple Macintosh, since the 2007 version, but there are also Windows versions of Stuffit, but SIT has so far there is no meaning.
SIT was the predominant archiving format on the Apple Macintosh platform for a long time. However, it has become increasingly important.
To create a SIT file you need an older version of StuffIt or Stuffit Deluxe. The newer and improved format SITX has replaced the old format. The new format offers not only high encryption (RC4 512Bit) but also special detection routines for various data types. For example, in the SITX format, jpegs, pdf files or MP3s can be compressed according to the manufacturer's statement using an optimized method.
To unzip a SIT file, you can also fall back on the free of charge provided by the manufacturer Smith Micro Stuffit Expander. On the Apple platform included the Stuffit Expander up to OSX 10.3, from OSX 10.4 you have to download it yourself from the manufacturer side.
Most often resolving problems with opening SIT files is very simple. Just install an appropriate program that supports such files. All of the listed programs support SIT files, but may vary in offered function and purpose. Some programs may be capable only of viewing contents of SIT files or offer file conversion options, but may not be capable of editing such files.
It is possible that although a compatible program has been installed on user’s system, it is not used by the system to open it. This may happen because no default application was associated with this type of files. To associate SIT files with given application, select "Open with" from drop-down menu (accessed by right-clicking on the file). Then select from the list the program or application you want to be used to open this type of file. If the Micro StuffIt Deluxe applications is not on the list, select "Browse" option in order to manually locate the directory where Micro StuffIt Deluxe has been installed.
Sometimes problems with opening SIT files may not lie with the application itself, but can arise due to other causes, such as: