- Close Outlook.
- Open the Registry Editor .
- If you using Office XP/2002, expand the branches to HKEY_CURRENT_USER Software Microsoft Office 10.0 Outlook Security If you using Office 2003, expand the branches to HKEY_CURRENT_USER Software Microsoft Office 11.0 Outlook Security
- Create a new string value by selecting New and then String Value from the Edit menu.
- Name the new value Level1Remove .
- Double-click the new Level1Remove to edit it, and enter the filename extensions you’d like to stop Outlook from blocking. Extensions should be typed in lower case, without the dots (.), and separated by semicolons (;). For example, type js;mdb;vbs to allow .js, .mdb, and .vbs attachments, respectfully.
- Click Ok and then close the Registry Editor when you’re done.
- The next time you restart Outlook, you’ll now be able to open previously-blocked attachments. (If an attachment is still blocked, you likely got the filename extension wrong.)
Reference: Force Outlook to allow EXE and MDB file attachments .
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