An A02 file is usually just the third block of a split archive and cannot open directly since it lacks the primary header, triggering errors like "cannot open as archive"; instead, place all volumes together and open the starter—either the .ARJ if it exists or the .A00 otherwise—so tools like 7-Zip or WinRAR can automatically read A01, A02, and the rest, with extraction errors typically caused by missing, incomplete, or corrupted parts; confirming sequential filenames and matching base names ensures you’re opening the correct starting volume.
To quickly confirm what an A02 is part of, alphabetize the directory so matching pieces line up, look for the same base name across files—`backup.a00`, `backup.a01`, `backup.a02`—and check for a main starter such as `backup.arj`; if it exists, you open the `.arj`, but if only `.a00` upward appears, you begin with `.a00`, using 7-Zip or WinRAR to test it; any missing sequence numbers or inconsistent naming usually indicate that a volume is absent or corrupted and must be replaced.
Describing A02 as "part 3" means it belongs to a multi-volume archive produced when a big compressed file is divided into `.A00`, `.A01`, `.A02`, etc. for easier transfer or storage, so A02 itself has no separate meaning and continues the same data, while the header and index live in the first volume or a main `.ARJ`, making A02 alone unusable; seeing matching files like `something.a00`, `something.a01`, and `something.a02` indicates a split set, and opening the first piece lets your extraction tool assemble the full archive.
An A02 file seldom opens alone because it’s a mid-archive volume, and formats store crucial metadata—header info, file tables, compression definitions, and CRC checks—at the beginning of the first volume, so when an extractor inspects A02 it sees no valid starting signature and issues errors like "archive corrupt"; putting all volumes in one folder and opening the true starter lets the tool read A01, A02, and onward seamlessly to reconstruct the original files.
When an extractor "uses" an A02 file, it’s not interpreting A02 as a full archive because all structure lives in the starter (`.ARJ` or `. If you treasured this article and you also would like to obtain more info about A02 data file nicely visit the web-page. A00`), and as the tool decompresses, it requests the next sequential piece—`.A01`, then `.A02`—to continue the data stream; if A02 is mislabeled, misplaced, or broken, the process halts with messages like "data error".