Opening 421 files
Did your computer fail to open a 421 file? We explain what 421 files are and recommend software that we know can open or convert your 421 files.
What is a 421 file?
Every day thousands of users submit information to us about which programs they use to open specific types of files.
While we do not yet have a description of the 421 file format and what it is normally used for, we do know which programs are known to open these files. See the list of programs recommended by our users below.
We are constantly working on adding more file type descriptions to the site - the current count exceeds thousand by far, and more information about 421 files will hopefully be added soon.
Software that will open, convert or fix 421 files
Try a universal file viewer
In addition to the products listed above, I would suggest that you try a universal file viewer like Free File Viewer. It can open over 200 different types of files - and very likely yours too! Download Free File Viewer.