Put every volume in the same folder and open the first part, usually .zip.001, .7z.001, or part1.rar. Do not rename the parts or mix them with other archives.
A split archive is one archive spread across several numbered files. It is different from a folder that merely contains several independent ZIP files.
Concept diagram using a three-volume 7z example. Real names and volume counts vary. Later volumes are not standalone archives; use the first volume for listing and testing.
- report.7z.001
The first volume for listing and testing.
- report.7z.002
Continuation data in the same directory.
- report.7z.003
Include the final volume from the same set.
Which file should I open first?
| Files in the folder | Open first |
|---|---|
| sample.7z.001, .002, .003 | sample.7z.001 |
| sample.zip.001, .002, .003 | sample.zip.001 |
| sample.z01, .z02, sample.zip | sample.zip |
| sample.part1.rar, part2.rar | sample.part1.rar |
These are filename examples. A bare .001 extension is not enough to identify the archive format. Keep the complete set, preserve the original names, and check the sender’s instructions. Do not extract each part separately or rename a later part to replace a missing one.
On September 12, 2026 we tested a generated 1,280,000-byte file, split at 512 KB into 7z volumes, using the official-installer v2.2.1 CLI on Windows 11 build 26200. Complete volumes passed the integrity test and extracted byte-for-byte; an isolated first volume failed the integrity test. This additional check covers that numeric 7z sample, not every split format or a new GUI walkthrough.
Identify the set before you do anything else
Independent archives
report.zip and photo.zip are separate files. You can batch extract them, but they are not one archive spread across volumes.
Split archive volumes
archive.zip.001, archive.zip.002, and archive.zip.003 are one archive with numbered parts. They must stay together.
Open the first volume
-
1
Keep every part in one folder.
Collect the numbered files into the same folder before opening anything. A missing part usually means the set is incomplete.
-
2
Start with the first volume.
Open the .001 or part1.rar file. Karuzip reads the later parts in order when they are present beside the first file.
-
3
Extract only after the set is complete.
Confirm that every expected part is present, then extract to a different empty folder so the result is easy to verify.
Frequently asked questions
What is a split archive volume?
A split archive is one archive spread across several numbered files, such as the first ZIP volume (.zip.001), the next ZIP volume (.zip.002), or the first split RAR volume (part1.rar). The first volume is the entry point.
Which file should I open first?
Open the first volume, usually the first numbered ZIP or 7z part, or part1.rar for split RAR sets. Keep the other volumes in the same folder so the app can read them in order.
Can I rename the volumes to shorter names?
No. Do not rename the parts while you are trying to open the archive. The numbering is part of how the archive is read.
Does one missing volume mean the archive is broken?
Usually yes. If one numbered volume is missing, you need to get the complete set again before extraction can succeed.
Can split archives still be password-protected?
Yes. A split archive can still require the correct password. Keep the full set together, open the first volume, and then enter the password when the extraction step requests it.
Official references
- 7-Zip: How to recover corrupted 7z archive — official split-volume and recovery notes (accessed August 13, 2026).
- 7-Zip FAQ — official notes about opening archives and extraction behavior (accessed August 13, 2026).
- 日本語版：分割ZIPの作り方・解凍方法 — original split-volume guide (accessed August 13, 2026).
Open the first volume and keep the rest together
Karuzip helps you keep split volumes organized before extraction. No ads, no bundles, and no app telemetry.
Download for Windows 10 / 11
Handle split archives as one input set
For extraction, the 2.2.3 development CLI fixes the mismatch between capability registration and execution when a non-first volume is selected. Integrity checking, listing, and inspection should still start from the first volume. Keep the complete ZIP/7z/RAR set together and prefer the first volume in a reusable script so the intended input is clear.
Before extracting, inspect and test the set. A missing part is not repaired by changing an extension or concatenating arbitrary files. A failure may report an incomplete set, a password requirement, or damaged content; preserve the input and investigate that specific result.
To create split output, archive.compress supports ZIP and 7z with one of eight sizes: 512k, 10m, 100m, 512m, 650m, 700m, 1g, or 2g. Values such as 1m and raw byte counts are not accepted. Check all generated parts before transferring the set.
Command example
karuzip-cli --json archive.test --archive ".\sample.7z.001"
karuzip-cli --json archive.extract --archive ".\sample.7z.001" --destination ".\split-out" --conflict-policy skipReplace the sample paths with your own test inputs. Keep global options before the action. Check the exit code and final JSON; these snippets are command examples, not proof that your archive will succeed.
Start with the CLI reference, then follow the actual local-command workflow for Codex, Claude Code, or DeepSeek Harness.
Content checked against the 2.2.3 development source on September 12, 2026. Public download: 2.2.5. Historical screenshots and measurements retain their original version. Editorial and testing policy.