Vista tip of the week: Change file type associations on the fly

I received an interesting tip this week from Dan via email regarding removing and changing Windows Vista file type associations on the fly. I have to admit, I had never heard of this one: You can remove a single file type association to more easily reassociate it. (You have to do this under admin rights, however.--Paul) At a command prompt (cmd.exe) type assoc.file_type= Where file_type is the extension of the file type for which you want to remove the application association. As an example, you could stop PHP files from opening with WordPad by typing assoc.php= and then hitting Enter. The next time you open a PHP file, you will be prompted to choose a program again. So this does work, but it's somewhat complicated. I recommend using the "Open with" trick instead. This can be used in two instances: When you want to change the association of a particular file type and when you want to just open a file with a different application on the fly. Here's how it works. Locate the document or other file you'd like to open. Hold down the Shift key and right-click the file. You'll see a new option, Open With, appear. The Open With option will have a sub-menu associated with it. You can choose an option from this menu or select Choose Default Program. From the Open With window, choose from the list of Recommended Programs. Or, click Browse to find a new program. When you locate a new program, it will appear in the Open With sub-menu and in the Open With dialog going forward. Note too the "Always use the selected program to open this kind of file." It's selected by default, so if you're not trying to change the association, make sure you uncheck it.

Paul Thurrott

July 7, 2008

2 Min Read
ITPro Today logo in a gray background | ITPro Today

I received an interesting tip this week from Dan via email regarding removing and changing Windows Vista file type associations on the fly. I have to admit, I had never heard of this one:

You can remove a single file type association to more easily reassociate it. (You have to do this under admin rights, however.--Paul)

At a command prompt (cmd.exe) type assoc.file_type= Where file_type is the extension of the file type for which you want to remove the application association. As an example, you could stop PHP files from opening with WordPad by typing assoc.php= and then hitting Enter. The next time you open a PHP file, you will be prompted to choose a program again.

So this does work, but it's somewhat complicated. I recommend using the "Open with" trick instead. This can be used in two instances: When you want to change the association of a particular file type and when you want to just open a file with a different application on the fly. Here's how it works.

Locate the document or other file you'd like to open. Hold down the Shift key and right-click the file. You'll see a new option, Open With, appear. The Open With option will have a sub-menu associated with it. You can choose an option from this menu or select Choose Default Program.

From the Open With window, choose from the list of Recommended Programs. Or, click Browse to find a new program. When you locate a new program, it will appear in the Open With sub-menu and in the Open With dialog going forward. Note too the "Always use the selected program to open this kind of file." It's selected by default, so if you're not trying to change the association, make sure you uncheck it.

About the Author

Paul Thurrott

Paul Thurrott is senior technical analyst for Windows IT Pro. He writes the SuperSite for Windows, a weekly editorial for Windows IT Pro UPDATE, and a daily Windows news and information newsletter called WinInfo Daily UPDATE.

Sign up for the ITPro Today newsletter
Stay on top of the IT universe with commentary, news analysis, how-to's, and tips delivered to your inbox daily.

You May Also Like