Error Message:

"you are attempting to open a file that was created in an earlier version of microsoft office. This file type is blocked..."

Word 2003 Fix:

In Word 2003, there are no trusted locations. You can create an exempt location to override the registry policy settings. To create an exempt location, follow these steps:


  1. Exit Word 2003.
  2. Click Start, click Run, type regedit in the Open box, and then click OK.
  3. Locate and then click one of the following registry subkeys:
HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Common
  • HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\11.0\Common
  1. Point to New on the Edit menu, and then click Key.
  2. Type OICEExemptions for the name of the key.
  3. Point to New on the Edit menu, and then click String Value.
  4. Type a string name, and then press ENTER. For example, type ExemptDirectory.
  5. Right-click the string name that you typed in step 7, and then click Modify.
  6. In the Value data box, type the path of the directory that contains the file, and then click OK. For example, if your document is in the C:\My Documents folder, type C:\My Documents in the Value data box.

    Note You must create the folder. Any subfolders are not automatically exempted. For any additional folders that you would like to make exempt, repeat steps 6 to 9 by creating string values such as "ExemptDirectory1," and "ExemptDirectory2."
  7. On the File menu, click Exit to exit Registry Editor.

Reference:
http://support.microsoft.com/kb/922849#w2003