Copy and paste this into the KEY_CURRENT_USER\Software\Microsoft\Office\10.0\Outlook\Security as per instructions above.
.ade;.adp;.asx;.bas;.bat;.chm;.cmd;.com;.cpl;.crt;.exe;.hlp;.hta;.inf;.ins;.isp;.js;.jse;.lnk;.mb;.mdb;.mde;.msc;.msi;.msp;.mst;.pcd;.pif;.prf;.reg;.scf;.scr;.sct;.shb;.shs;.url;.vb;.vbe;.vbs;.wsc.sf;.wsh
This will allow all blocked attachements in, not sure if you are storing your mail in a .PST file but you will be able to see them all if running off an Excahnge Server.
If you do not it could be that your mail server is blocking the attachment too.
Hope this helps,
Iain