WARNING – FOLLOWING THESE INSTRUCTIONS COULD LEAVE YOUR COMPUTER OPEN TO ATTACK FROM VIRUSES ETC. CHIMPYTECH.COM CAN ACCEPT NO RESPONSIBILITY FOR ANY DAMAGED CAUSED TO YOUR SYSTEM FROM THE IMPLEMENTATION OF THESE INSTRUCTIONS.
In an attempt to provide an improved level of security for E-mail users, Microsoft decided a few years ago to block certain attachments when received in Outlook.
As Outlook has no in-built virus scanning capability it blocks ALL attachments from the barred list whether they contain a virus or not, which can be a real nuisance if you have received a file which you know to be clean but are unable to access. With a small registry tweak it’s possible to create a list of allowed attachments that Outlook will not block, and as with all tweaks that involve the registry we recommend that you only make the changes if you’re confident of what you’re doing, and you have made a back-up of the registry. Make sure Outlook is closed, and that you are logged on with an account that allows you access to the registry editor.
- Click ‘Start’, then ‘Run’ and type ‘regedit’ into the run command dialog.
- Depending on your version of Outlook you will need to find the following registry key
- [HKEY_CURRENT_USERSoftwareMicrosoftOffice9.0OutlookSecurity](Outlook 2000)
- [HKEY_CURRENT_USERSoftwareMicrosoftOffice10.0OutlookSecurity](Outlook 2002)
- [HKEY_CURRENT_USERSoftwareMicrosoftOffice11.0OutlookSecurity](Outlook 2003)
- Select ‘Edit’ then ‘New’ and ‘String Value’ from the menu bar.
- Now you will need to name your value – Level1Remove
- To enter allowed attachments, double click the value you just created, and enter the extension of the files you want to allow’ (including the ‘dot’ e.g. .bat)
- If you want to enter multiple extensions, create a list with semi-colons as separators. (e.g. .bat;.mdb;.exe;.vbs)
- Click ‘OK’ once your list is complete, and close the registry editor.
Now when you start Outlook, you will have access to attachments bearing the extensions in your allowed list.
This is a list of blocked attachments at the time of writing, security updates issued by Microsoft my add to or remove items from this list, so please don’t treat it as a definitive list.
.ade – MS Access project extension
.adp – MS Access Project
.asx – Windows media file
.bas – Visual Basic code module
.bat – Windows / MS-DOS batch file
.chm – HTML Help file
.cmd – Windows NT command script
.com – MS-DOS program
.cpl – Control Panel extension
.crt – Security certificate
.exe – Executable program
.hlp – Help file
.hta – HTML program
.inf – Setup file
.ins – Internet naming service file
.isp – Internet communication settings file
.js – JScript file.
.jse – Encoded JScript File
.lnk – Shortcut
.mda – MS Access add-in
.mdb – MS Access program
.mde – MS Access MDE Database
.mdt – MS Access workgroup information
.mdw – MS Access workgroup information
.mdz – MS Access wizard program
.msc – MS Console document
.msi – MS Windows installer package
.msp – MS Windows installer patch
.ops – Office XP settings
.pcd – MS Visual compiled script or Photo CD Image.
.pif – MS-DOS shortcut
.prf – MS Outlook profile settings
.reg – Registry entries
.scf – Windows explorer command
.scr – Screen saver
.sct – Windows script component
.shb – Shell scrap object
.shs – Shell scrap object
.url – Internet shortcut
.vb – VBScript file
.vbe – Encoded VBScript file
.vbs – VBScript file
.wsc – Windows Script component
.wsf – Windows Script file
.wsh – Windows Script host settings file