An A01 file tends to be the second unit in a split archive, and identifying what it belongs to involves checking for matching files—if .ARJ, .A00, .A01, .A02 appear together, it’s likely an ARJ set where .ARJ is the starting file; if .ARJ is absent but .A00 exists, .A00 is typically the opener, and using 7-Zip or WinRAR on that file confirms the archive, with extraction failures commonly due to missing or non-continuous segments, showing A01 is merely one of the required parts.
A “split” or “multi-volume” archive is created when one archive is split into smaller files like `backup.a00`, `backup.a01`, and `backup.a02` to bypass size limits, and in this setup A01 is merely the second segment that can’t function by itself because essential header/index info resides in the first volume or an `.ARJ` controller file; extraction must begin with the main or first part, and if any volume in the chain is absent or corrupted, errors such as “unexpected end of archive” appear because the tool can’t reconstruct the full archive.
You often see an A01 as many archivers naturally label sequential parts where A00 begins the sequence and A01 follows, ensuring ordered extraction; ARJ sets are a classic example, with .ARJ providing the table of contents and the A00/A01 files storing the content, and many backup utilities likewise use “Axx,” meaning A01 appears whenever more than one volume is needed and may cause confusion when the core starter file is absent.
To open or extract an A01 set correctly, know that A01 doesn’t contain the archive’s beginning, meaning extraction must start from the file holding the archive header; check that all pieces share the same base name and sit in the same directory (`backup. If you are you looking for more info in regards to A01 file viewer review our own website. a00`, `backup.a01`, `backup.a02`), then pick the proper opener—`.ARJ` if available, otherwise `.A00`—and load it in 7-Zip/WinRAR, which will automatically chain through the remaining parts, with errors like “cannot open as archive” often caused by missing or corrupted volumes or an unsupported splitting method.
To confirm what your A01 belongs to in half a minute, sort the directory so names line up to group related parts, then look for a .ARJ plus matching A00/A01/A02 files—an indicator of an ARJ multi-volume archive with .ARJ as the starting file; if only .A00 and higher exist, begin with .A00 and test it using 7-Zip/WinRAR → Open archive, checking afterward that the numbering has no gaps and the volumes are similar in size since missing chunks are the usual failure point.
