If you ever received an email with an attachment that contains the .exe, .url, .reg file extension in Outlook you will get a nice little warning prompt saying Outlook blocked access to the following potentially unsafe attachments. By default Outlook blocks these for security reasons. Luckily there is a free tool that lets you unblock these. Here is how to unblock Outlook 2010 blocked attachments with Attach Unblocker.
Outlook 2010 Blocked Attachments Fix
All you have to do for this fix is download and install Attach Unblocker. Next open Outlook 2010 by going to the Start Search and searching for Outlook 2010. Once Outlook is open locate the Unblock attachments icon in the ribbon interface. Click on it.
When you click on it you will see a Attach Unblocker menu. Here you will want to enter the type of attachments you want to unblock by putting the extension in the box next to the Add button. Then click the Add button to add them to the list.
Once you added a few file extensions to your list you will want to click Apply at the bottom of the menu.
You will be prompted to restart Outlook for the changes to take effect.
Click ok to the warning prompt and close Outlook. Open it back up and try opening the attachment you were denied access earlier. To let Outlook block certain file extensions again just go back to the Attach Unblocker menu and select the extension you want to remove. Then Click the Remove button and click Apply. You will need to restart again.
Just make sure you trust the files that you are unblocking. Just incase they might be infected or execute malicious code. Another note, if you use Outlook with Gmail, Yahoo, or MSN you will not be able to send unsafe files because of the restrictions in place with the online email clients.