This is a registry fix to a constant problem sending mdb files using outlook, the recipient does not get the file as outlook has blocked the display. I take no credit for this fix for the full article see this reference http://www.slipstick.com/outlook/esecup/getexe.asp. The following is an extract from that page for my reference.
Outlook 2007, Outlook 2003, Outlook 2002 and Outlook 2000 SP3 (but not Outlook 98 or earlier Outlook 2000 versions) allow the user to use a registry key to open up access to blocked attachments. (Always make a backup before editing the registry.) To use this key:
1.Run Regedit, and go to this key:
HKEY_CURRENT_USERSoftwareMicrosoftOffice10.0OutlookSecurity (change 10.0 to 9.0 for Outlook 2000 SP3 or to 11.0 for Outlook 2003, 12.0 for Outlook 2007 )
2.Under that key, add a new string value named Level1Remove.
3.For the value for Level1Remove, enter a semicolon-delimited list of file extensions. For example, entering this:
would unblock Microsoft Access files and Internet shortcuts. Note that the use of a leading dot was not previously required, however, new security patches may require it. If you are using “mdb;url” format and extensions are blocked, add a dot to each extension. Note also that there is not a space between extensions.