Re: Word document extension issue

From: Jay Freedman (jay.freedman_at_verizon.net)
Date: 03/26/04 

Date: Thu, 25 Mar 2004 22:45:53 -0500

It's nothing very mysterious. If you open any Word document in a hex
editor, the first 16 bytes have these hex values:

D0 CF 11 E0 A1 B1 1A E1 00 00 00 00 00 00 00 00

When you double-click an "unknown" file, Explorer checks the start of
the file against a list of known patterns. If it recognizes the
pattern, it "helpfully" uses the proper application.

To test this, I took a Word file and changed its extension to "fred".
As you found, it became "unknown" but still opened in Word. Then I
used a hex editor to change the first byte from D0 to A0. Now Windows
couldn't recognize it. Finally, I changed the byte back to D0, and the
file again opens in Word.

<anonymous@discussions.microsoft.com> wrote:

>Hello Charles,
>
>Thanks for the reply. Yep the same thing happens with Word
>closed. Have you been able to reproduce the problem? You
>can right click create a new word document and then call
>it test.tango - then it changes to an unknown file-type
>icon, however Word still opens it up? Strange issue, any
>other ideas would be helpful, this is to explain to one of
>our customers. Thanks.
>
>
>>-----Original Message-----
>>I don't know. Do you get the same effect if you rename
>a .doc file in
>>Windows with Word closed? I suspect that MS may have some
>kernel of pattern
>>recognition for its own file types in Windows. Just
>speculating, though.
>>--
>>
>>Charles Kenyon
>>
>>See the MVP FAQ: <URL: http://www.mvps.org/word/> which
>is awesome!
>> --------- --------- --------- --------- --------- ------- 

--
Regards,
Jay Freedman
Microsoft Word MVP        FAQ: http://www.mvps.org/word

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