MS Outlook 2000 - unsafe attachments

Your best source of information about Outlook, is Slipstick.com.
Here's a good discussion:

http://www.slipstick.com/addins/utilities/attsecup.htm

(There are no spaces in the URL)

1 Exit Outlook, if running.

2 Click the Windows Start button, and then click Run.

3 In the Open box, type regedit, and then click OK.

4 Navigate to the following registry key:

HKEY_CURRENT_USER\Software\Microsoft\Office\10.0\Outlook\Security

5 Click the Edit menu, click New, and then click String Value.

6 Type the following name for the new value:

Level1Remove

7 Press ENTER.

8 Right-click the new string value name, and then click Modify.

9 Type the extension of thefile type that you would like to access with Outlook 2002 as follows:

.exe

To specify multiple file types, use the following format:

.exe;.com

10 When finished, click OK.

11 Exit the Registry Editor program.

When you start Outlook 2002, the file types specified in the Windows Registry are accessible.

If you need more help look up this article at MS knowledge base Q290497

Sometimes it is the server that is set to strip out exe files so that viruses are not transmitted and then executed.

If you are not administrator or the above does not help, then the easiest workaround is to tell your firend to send any attachments as .ZIP or whatever is not set to be blocked. He or she can rename the file to whatever extension they like; you need to rename the file and then run it.