Skip to main content

Common errors

Purrchiver tries hard to give you a specific, actionable error message for every failure case — not just “extraction failed.” This page is the catalog: every error you might see, what it means, and what to do about it.

If you hit something not on this page, email corey@purrchiver.app — I’ll add it.

Opening errors

You opened a Windows installer (.exe / .msi)

Purrchiver tells you Windows executables aren’t archives — they’re installation programs that need to run on Windows.

What to do:

  • If you wanted the installer’s contents (e.g., to extract files embedded inside), use a Windows VM or a tool specifically for unpacking installers (Universal Extractor, 7-Zip on Windows). Most modern Windows installers (.msi, NSIS, Inno Setup) can be unpacked by specialized tools — Purrchiver isn’t one of them.
  • If you got the .exe by mistake (someone meant to send you a .zip), ask them to re-send.

You opened a disk image (.dmg)

Purrchiver tells you DMG files are disk images, not archives, and points you at Finder (double-click to mount) or Disk Utility. Disk images aren’t handled inside Purrchiver — they’re a macOS native surface.

You opened a StuffIt archive (.sit / .sitx)

See the dedicated page: StuffIt files.

Short version: StuffIt is an abandoned format. Use The Unarchiver (free from the Mac App Store) for the one-time extract.

The file’s header doesn’t match any format Purrchiver recognizes

Purrchiver tells you the archive couldn’t be opened. Possibilities:

  • The file is corrupt — try downloading it again.
  • The file is an unsupported format — see Format support for the list of skips.
  • The file has the wrong extension — .zip could actually be a renamed .tar.gz, etc. Try opening in another tool to confirm.

Purrchiver couldn’t read the file (unreadable file)

Purrchiver couldn’t reach the file — it shows that the file “may be missing, moved, or inaccessible.” Purrchiver is sandboxed and only gets access to files you hand it through the standard macOS open panel, so this usually means Purrchiver doesn’t currently have access to where the file lives. Either:

  • The file is in a protected location (Documents, Desktop, Downloads, iCloud Drive) that Purrchiver hasn’t been granted access to yet.
  • Fix: Re-open the file (or its folder) through Purrchiver’s open panel, or use the folder picker to grant access to the folder it’s in. That security-scoped grant is how a sandboxed app like Purrchiver gains access — there’s no per-app toggle in System Settings for it.

If the file is somewhere unusual (a network mount, external volume with write protection, etc.), Purrchiver may still get denied even after you grant access. Try copying it to your Desktop first.

Multi-part errors

A part is missing from the set

Purrchiver checks the set before reading and tells you what’s wrong:

  • A middle part is missing — it names the gap (e.g. “some parts are missing (003)”).
  • The final part is missing — it says the set is incomplete; for 7z it even estimates how much data is still missing.
  • A part was renamed so the numbering no longer matches — the set can’t assemble (Purrchiver finds parts by their original names).

What to do:

  • Keep every part in one folder with its original filename.
  • Add the missing part(s), then re-open any one of them.
  • If a part is genuinely gone, re-download or re-acquire the full set.

See Multi-part archives for the full story.

Password errors

Incorrect password

Purrchiver tells you the password didn’t match. Either:

  • Typo — type it again. Check Caps Lock.
  • Wrong password — confirm with whoever sent you the archive.
  • The archive’s encryption is broken / corrupt — try opening it in another tool (7-Zip on Windows, 7z x on Linux) to confirm.

Purrchiver cannot recover passwords. There is no “forgot password” feature.

Non-ASCII passwords aren’t supported

Purrchiver tells you that Unicode-character passwords aren’t supported in this release — only ASCII characters work. If the archive’s password contains non-ASCII characters, open it with a different tool.

The archive has header encryption

For 7z and RAR with header-encrypted entries, the filename list is itself encrypted. Purrchiver shows a password prompt before listing the contents — that’s normal. Enter the password and the contents appear.

Extraction errors

The archive is corrupt or truncated

Purrchiver tells you reading an entry failed. The archive’s bytes don’t match what its metadata says they should be. Common causes:

  • Download was interrupted — re-download.
  • Disk error on the source — try copying the file again from its source.
  • Multi-part with a damaged part — try extracting the parts individually to confirm which one is damaged; re-download just that part.

If Purrchiver was partway through when it hit the corruption, the entries it had already extracted are intact in the destination.

Purrchiver can’t write to the destination

macOS won’t let Purrchiver write to the chosen folder. Either pick a different destination, or use the folder picker to grant Purrchiver access to the destination folder. (Purrchiver is sandboxed, so it gains write access through that security-scoped grant — not through a System Settings toggle.)

The archive looks like a decompression bomb

The archive’s declared total extract size is at least 100× its compressed size (with a 10 MB declared-size floor), or the declared extract size won’t fit — it’s larger than about 90% of the free space on the destination. Purrchiver shows you a preflight prompt with the numbers and asks whether to proceed. See Decompression-bomb safety for the full explainer.

If you proceed anyway and the extract overshoots the 50 GiB aggregate cap, Purrchiver aborts mid-stream rather than fill your disk.

Creating errors

The two password fields don’t match

The Create Archive sheet keeps the Create button disabled until both password fields contain the same text. Re-type one to match the other.

The output filename already exists

Purrchiver won’t silently overwrite an existing file. Confirm to replace, or change the output filename.

Purrchiver can’t write to the output location

Same as the extraction equivalent. Pick a different location, or use the folder picker to grant Purrchiver access to the output folder.

Archive verification failed

Purrchiver tried to verify the archive it just wrote, and the verify failed. The atomic swap was aborted — the new archive was not written to your chosen destination. Your source files and any pre-existing file at the destination are untouched.

This is rare. If it happens, please email corey@purrchiver.app with:

  • The format you were creating
  • Whether encryption was on
  • Whether split-volumes was set
  • Roughly how large the source files were

Editing errors

Edit mode isn’t available for this format

Edit mode only works on formats Purrchiver can write: ZIP, IPA, APK, 7z, AAR, AEA, ISO 9660, and CPIO. Read-only formats (RAR, the tar family, .deb, .rpm, XIP, PKG, MPKG, XAR, .cab, .lha, .warc, .Z) don’t expose the Edit toolbar button.

To “edit” one of these, extract everything to a folder, make your changes there, and create a new archive (probably as ZIP or 7z).

Save failed during the rewrite

If verification or the atomic swap fails during Save, the original archive on disk is left untouched — Purrchiver writes to a temp file and only swaps in the new archive after every entry verifies. Your edits in the window are still in memory; Save again, or close and re-open the archive to discard.

Other

The archive has too many entries

Purrchiver caps the in-memory entry list at 1,000,000 entries to keep memory predictable. Archives declaring more than that are rejected at open time as a safety measure.

If you’re hitting this on a real archive, email corey@purrchiver.app with the archive size and entry count if you can determine them — we want to know about real-world cases.

You cancelled an operation

You clicked Cancel during a long operation. The Activity row shows “Cancelled”.

  • For extractions: files already written are kept (we don’t roll back partial extracts — finding nothing in your destination folder when you cancelled a 90%-done job would be worse than finding the partial result).
  • For compresses: the partial output file is deleted (you don’t want a half-written archive).
  • For edits: the original archive is untouched (the rewrite hadn’t finished and verified yet).

How to report a bug you don’t see here

  1. Open Console (Spotlight → Console).
  2. Pick Crash Reports in the sidebar (if Purrchiver crashed) OR filter for “purrchiver” in the search field (for non-crash logs).
  3. Email what you find to corey@purrchiver.app along with:
    • macOS version
    • Purrchiver version (Purrchiver → About Purrchiver)
    • What you were doing when the problem happened
    • What you expected vs. what happened

Email goes directly to me. There’s no support queue, no chatbot.