Network Productivity Group

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The tip...

Technical tip #40, April 26, 2002, What to do when you try to open an attachment or file and get the "Open With" dialog box.

This tip is in response to a request and revolves around the dialog box you see here:

Depending on how your Windows Explorer or My Computer is set up you may or may not see at the end of a filename three characters called "an extension".  Windows uses the extension to decide what program to use to open the file if you ask for it to be opened.  For example, if you open a file with the ".doc" extension, Windows will normally "launch" WORD and WORD will open that file.

If you open an e-mail attachment (or any file really) for which Windows has not "registered" a "handler"  you will see the Open With dialog box.  First and foremost, unless you are positive which program will open the file, check off the "Always use this program" box.

Notepad is the most flexible of programs when it comes to opening unrecognized files.  Notepad may not be able to open it or it may show you only garbage or it may show you enough that you can guess what to do with the file.

Generally, receiving a file like this means that someone has sent you a file created with software you do not have.  If the file is text (Word Perfect or Lotus Smart Suite or other editor) or a spreadsheet (as in Excel, Lotus 1-2-3, etc.) you can often open them with either WORD or Excel.  If they are images, most image programs are highly flexible and will open almost any file.  There are also marvelous image translators.  I use one called Multimedia Manger.  See  

The problem of course is how do you know what the file is if you can't see the last three little characters?  If you open either Windows Explorer or My Computer you should see a toolbar item called View.  Click on that and you will see Folder Options.  Click on that and you will see:

If you select the View tab you will see:

Notice the checkbox for "Hide file extensions for known file types".  If you check this off and select Apply you will now see the three little characters.  While they are often undecipherable they may help you to determine what the file might be and what to try to use to open it.

What to do if you've opened the file, did not check off "Always use this program" and it was the wrong choice?  Highlight the file name in Outlook, Outlook Express, My Computer, Windows Explorer, etc., and press and hold the SHIFT key.  Now RIGHT click the filename.  In the resulting pop up menu you should see "Open With".  Selecting this will take you back to square one, the Open With dialog box and you can try again.  Check off "Always use" please!

You can "permanently" delete this file association.  Refer back to the first "Folder options" image above and you will see a "File Types" tab.  If you open that you may be able to find the file by the three character extension and edit its "Open With" association and delete or change it.  The trouble with this I've found is that once the association has been made it becomes problematic to find the file type.  Careful hunting is suggested because the only other option is to edit the System Registry, a practice I do not encourage.


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