Associate unknown file types and gain right mouse control (InfoWorld)

February 5, 1996
Associate unknown file types and gain right mouse control

In the past three weeks, I've described new ways to use your right mouse button under Windows 95. The first two columns explained tricks involving the Send To command you see on the pop-up menu (called the context menu) that appears when you right-click a file in the Explorer. Last week, the subject was how to add whole new actions to the context menu for specific file types, such as .TXT or .DOC files. (If you missed those columns, see Reader resources, page 88, to order back issues.)
In the final column of this series, I'd like to show you the most powerful secret of all. It's an undocumented way to define new context menu actions that take effect not just for a single file type but for all file types. Even better, you can define actions that show up only when a file you right-click isn't associated with any application at all -- a so-called Unknown file type.
This latter action is most useful when you encounter, for example, files named README.1ST, MANUAL.BIN, or OUTPUT.LOG. Would you normally try to inspect these files by opening them in Notepad? That won't work if the files are anything other than plain text files less than 50KB in size.
It would be much better to be able to open such files in your favorite hexadecimal editor, which is capable of reading any file, regardless of the format or lack of one. In fact, you may want to have your hexadecimal editor appear in your context menus for all file types you might right-click. But Win95 provides no easy way to add a context menu action for all file types, unless you figure that defining an action manually for 50 or 60 file types is easy.
Here's how to add both the Unknown file type and the All file type to the list of file types you can associate with applications:
Step (1) Use Notepad or any text editor to create a text file called ALLTYPES.REG, containing the following five lines:
REGEDIT4 [HKEY_CLASSES_ROOT\Unknown] "EditFlags"=hex:02,00,00,00 [HKEY_CLASSES_ROOT\*] "EditFlags"=hex:02,00,00,00<$E""><$V10>
Step (2) Save ALLTYPES.REG in any folder you like or on the Desktop. Exit your text editor. Find ALLTYPES.REG on your Desktop or in the Explorer and right-click it. On the context menu that appears, click Merge.
That's it. You've just added four lines to your Registry. The next time you click View, Options, File Types in the Explorer, there will be two new file types with which you can associate actions. The one at the top of the list will be file type "*". The other, farther down the list, will be file type Unknown.
You can associate WordPad with all Unknown file types. WordPad can open files of almost any format except executables, unlike Notepad, which chokes on nontext files. If you have a hexadecimal editor, use that in the above example instead.
In the Explorer, click View, Options, File Types. Select Unknown in the scrolling Registered File Types list. Click the Edit button, then the New button. In the Action box, type Open in WordPad. In the Application box, type "C:\Program Files\Accessories\Wordpad.exe". (The quotes are necessary because there is a space in the Program Files folder name.) Close all the dialog boxes. Now right-click any unassociated file type, and you should see a new Open in WordPad option on the context menu.
This technique offers you unlimited control over the powers of your right mouse button.

Brian Livingston is the coauthor of the new Windows 95 Secrets and author of three other Windows books (IDG Books). Send tips to brian_livingston@infoworld.com or fax: (206) 282-1248.
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