The next time you double click a file with that file extension in Outlook, it will directly open with the newly selected program. When you’ve selected the application that you want to open it with, make sure the option “Always use this app to open files” “Always the selected program to open this kind of file”. When multiple applications are already associated with that file type, choose “Open with” and then select “Choose another app” or “Choose default program…”. Quickly change the default via Open With…Ī quick way to change the default application a certain file type opens with is to right click on it (after saving your attachment to disk first) and choose “Open with…”.

Outlook simply tries to open it with whatever application you have set as the default for that file extension in Windows Settings or Control Panel. That is not something controlled by Outlook but by Windows.

How can I tell Outlook which program to open the attachment with? As I want to read and not edit the pdf-file, I’d much rather open it with Adobe Reader instead. Eventually, this will work for most pdf-files but loading Photoshop takes a while and only allows me to view a single page at once. Similarly, when I double click on a pdf-file, it tries to open it with Adobe Photoshop. When I double click on a Word attachment, Outlook tries to open it with “Windows Photo Viewer” which obviously fails.

Pdf viewer for windows mobile 2003