Remove one attachment from a forwarded email

Version: Outlook 2002

Scenario:
2 users have an HTML or Plain text email with several attachments. Users
forward the email to someone else but want to remove one (or more) of the
attachments before sending.

User 1 right clicks on the attachment and chooses CUT. When email is
received, the cut attachment is still attached. In tests, I found out that
CUT does not remove the attachments, but REMOVE does. Advise user to choose
REMOVE instead.

Several months later, User 2 right clicks on the attachment and chooses
REMOVE. Attachment is still attached when received. I retest and cannot
duplicate on any other machine.

Both users are clicking Forward before REMOVING or CUTTING the attachments.

Why isn't REMOVE working for User 2? What steps should I take to
troubleshoot this?