Recently one of the developer sent out an email to me stating the he face 'new' issue with Outlook 2007, which blocks access to some of the mail's attachments. When they try to access the attachment they get the following error message “Outlook blocked access to the following potentially unsafe attachments: []”. He also complained that the Outlook blocks the specific attachment; he cannot save, delete, open, print, or can’t work with the attachment in Outlook. For him it’s quite annoying as he is using Outlook from version 2000 onwards (2000, 2003 & 2007), but he noticed this strange behavior in 2007 and want to know that it might be a bug or new security feature with Outlook?

Later i checked regarding the same and responded him to refer the support KB which states methods that he can use if he have to open an attachment that is blocked in Outlook. Additionally, this article contains information about the kinds of attachments that Outlook blocks. Per KB’s excerpt, it’s bit clearly mentioned that “All versions of Outlook since Outlook 2000 Service Release 1 (SR1) include a security feature that blocks attachments that might put your computer at risk for viruses or other threats. Although Outlook blocks access to the attachment, the attachment still exists in the e-mail message…”.

Also guided him to check whether the mail contains the actual attachment or just a shortcut to a file in Outlook(if we right-click the original file, drag the file to the Inbox folder in Outlook, and then click Send with Shortcut), which may also prompt outlook to throw this message.

Please note: Shortcuts that have file name extensions of .lnk or .url are Level 1 e-mail attachment types and are not available to the recipient.

Hope this helps.