Problem

The file download action is a user preference and depends on the user’s browser settings.  You can set certain file types or file extensions to open automatically after the download has completed.

In order for certain files to open automatically, a default program must be specified.  

Resolution

If you are using Mozilla Firefox, the download settings are under Options -> Applications.  Once you choose the corresponding file type, click on the Action drop-down menu and choose between: Always ask, Save File or the program you want use to auto-open a file.

 For IE, the settings depend on the Operating System and the IE version.

 On IE 9 on Windows 7, there is a check for “Always ask before opening this type of file” for a particular file type or file extension, on the File Download dialog box when you download the file. If you uncheck it, you will no longer see the File Download confirmation dialog. Please note that the particular file type needs to be downloaded and saved at least once.

 The files will be automatically downloaded once you click on the link, and then opened for you as your chosen preferred action.

Another way of disabling the “Always ask before opening this type of file” is trough the registry key. Basically, you go to the registry key...

 HKEY_CURRENT_USER \Software\Microsoft\Windows\Shell\AttachmentExecute\{0002DF01-0000-0000-C000-000000000046}

 ...(create this key if it doesn't exist) and add a zero-byte REG_DWORD value under it, named appropriately for the file type you want to open.  Like this...

 [HKEY_CURRENT_USER\Software\Microsoft\Windows\Shell\AttachmentExecute\{0002DF01-0000-0000-C000-000000000046}]

"AcroPDF.PDF.1"=dword:00000000

The tricky part is determining the proper name to give to this registry value. You need to look at the key names under HKEY_CLASSES_ROOT and maybe try different ones associated with the file type you want to open. In the case of PDF files (with Adobe Reader) it is AcroPDF.PDF and AcroPDF.PDF.1, for example.

You can also distribute this reg value via group policy to all users who would not like to be prompted to open/save files.

For IE 8, 7 or 6 on Windows XP: Open any folder with Windows Explorer or open My Computer -> Tools -> Folder Options -> File Types tab. This tab lists every file type associated with Windows. Locate and highlight the file type or extension that you want to open on download and click on Advanced button. In the Edit File Type window, check the 'Confirm open after download check box'.

You should also adjust the IE download settings under IE Tools menu -> Options -> Security -> choose the proper zone -> Custom level -> Downloads -> ‘Automatic Prompting for file download’