https://www.sitepoint.com/outlook-unblock-unsafe-attachments/
There’s a vast range of desktop and online email clients but it’s hard to beat Microsoft Outlook. The application has been around since 1997 and, despite a few dodgy decisions regarding HTML rendering, it’s still the email client of choice for me and many others.
Unfortunately, there’s an Outlook message web developers hate:
Outlook blocked access to the following potentially unsafe attachments…
Thanks Microsoft. I know why you’re blocking that JavaScript file, but I know what it is and I really, really want it.
Outlook doesn’t allow you to unblock unsafe attachments. Fortunately, there is a way to obtain the file and prevent the embarrassment of requesting a renamed version. Before we start…
tip: BIG REGISTRY WARNING!
We’re about to delve into the Windows registry. Please move along if you don’t know what the registry is or have never dabbled with it before. It’s a dangerous place — once false move and your PC will explode.
The fix will also reduce Outlook security settings. That’s not a problem for someone with reasonable IT knowledge, but it’s not for everyone.
Still here? OK, here’s what you do:
1. Close Outlook
2. Run regedit.exe
Navigate to:
HKEY_CURRENT_USERSoftwareMicrosoftOfficeXX.XOutlookSecurity
Where XX.X indicates your version of Outlook:
- 14.0 for Microsoft Office 2010
- 12.0 for Microsoft Office 2007
- 11.0 for Microsoft Office 2003
- 10.0 for Microsoft Office 2002
- 9.0 for Microsoft Office 2000
3. Create a new value
Create a new string value key in that location named:
Level1Remove
4. Choose your ‘safe’ file types
Edit the key and enter a list of attachment extensions you want to unblock. Each should start with a period and be separated with a semi-colon. For example…
To unblock JavaScript files only, enter:
.js
To unblock JavaScript, VBScript, and exe files, enter:
.js;.vbs;.exe
Click OK to save the value then exit regedit.
5. Restart Outlook
The attachment should be magically unblocked. Try rebooting if that’s not the case.