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Myth Busting about Office document formats

Even after 15 years, there’s still misinformation about the ‘new’ Office document formats .docx .xlsx etc. We’ll explain these myths and how you can easily disprove them yourself.

Most of these myths surround the use of ZIP compression to make the document files smaller.  Folks have jumped to wrong conclusions after hearing about ZIP.

Not like the old .doc .xls or .ppt formats

The new document formats are NOT just old documents in a ZIP container.  This myth says that .docx  is just a .doc file, compressed with ZIP and renamed .docx.  Bollocks … total bollocks.

The new Office formats are fundamentally different using XML structures before compression.

Password protection is weak – not!

ZIP files have a password option but it’s very weak and relatively easy to crack.  This has led to the myth that Microsoft Office password protection is also weak.  Again, Bollocks … total bollocks.

The password protection in Office documents is NOT the zip password system.  

Microsoft Office encrypts the entire documents contents to a high level – usually AES-128 or AES-256 which is enough for government and defense security.

Be your own myth buster

Anyone can bust these myths themselves, you don’t need to believe us.

Take a .docx file, rename to .zip then extract the contents to your computer- you’ll be able to see the XML files that make up the document.

That’s completely different to the pre-2007 formats.

Open one of the .xml files (like document.xml) to see how a modern Office document is made.

It looks a little like a HTML web page with <tags> because both new Office documents and HTML are types of XML.

The ZIP password myth is busted in a similar way.  Make a password protected Office document, rename to .ZIP then try to open it.  You can’t!  There’s a ‘corrupt or damaged file’ error because the whole package has been encrypted so only the correct password can open it.

Why Old Office documents should be banned
Bulk conversion of old Office documents to new formats
Can I use old Office with Windows 10 or 11?
Free and secure conversion of .doc .xls or .ppt to the newer Office formats

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