How to open .BOO files on Windows
To open .BOO files on Windows, if you expect an archive: try opening the .BOO file with ZipZag (as referenced for BOO archives).
Step-by-step instructions
- If you expect an archive: try opening the .BOO file with ZipZag (as referenced for BOO archives).
- If it does not open as an archive, open it in a text editor (Notepad, VS Code) and check whether it looks like Kermit BOO text encoding (printable ASCII with an initial line indicating an original filename).
- If it appears to be Kermit BOO encoding, use a Kermit/BOO decoding workflow (from the Kermit toolchain for your platform) to convert it back into the original binary file.
Common issues
The .BOO file opens as gibberish or won’t “run”
Kermit BOO files are meant to be decoded back into the original binary; viewing them directly shows encoded text, not the usable program.
- Open the file in a text editor and confirm it is printable ASCII and appears to be a Kermit BOO encoding (often with an initial line indicating the original filename).
- Use a Kermit/BOO decoding tool to convert it back into the original file, then open/run the restored file with the correct program for that file type.
An archive tool says the .BOO file is not a supported archive
.BOO is not universally an “archive”; it may be Kermit BOO-encoded binary or a different .boo usage such as source code.
- Try opening it as plain text to determine whether it is Kermit BOO encoded text or Boo source code.
- If you specifically expected a BOO compressed archive, try ZipZag on Windows (commonly referenced for BOO archives); otherwise use Kermit BOO decoding instead.
Decoded output is corrupted or the filename is wrong
BOO decoding depends on intact text content; line-ending changes, truncation, or copy/paste transfers can break the encoding. The original filename is typically stored in the first line of the BOO file.
- Re-download or re-transfer the .BOO file using a method that preserves the exact text (avoid copy/paste; use file transfer).
- Ensure the decoder is treating the input as text and that the first line (original filename line) is intact before decoding again.
Confusion with Boo programming language files (*.boo)
Some systems associate .boo with the Boo programming language (a text source file) and may not recognize it as Kermit BOO encoding.
- Open the file in a text editor: Boo source looks like normal code, while Kermit BOO is an encoding block intended for decoding to a binary.
- If it is code, keep it as text and use developer tooling; if it is Kermit BOO, use a BOO decoder workflow instead of code tools.
Still can’t open your .BOO file?
Recover a deleted or lost .BOO file
If the file was deleted by mistake or the drive was formatted, data recovery software may be able to get it back. Stop writing to that drive right away, because new data can overwrite what you want to recover.
Windows software that recovers deleted or lost files from PCs and external drives such as HDDs, SSDs, USB drives and memory cards, after deletion, formatting or a crash.
Wondershare RecoveritWindows and Mac software that recovers deleted or lost files from computers and external drives such as HDDs, SSDs, USB drives and SD cards.
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Security note
Kermit BOO files are commonly used to distribute binary programs; after decoding, the output may be an executable. Treat the decoded file as untrusted until you know its origin and purpose.