The recipient receives an "Outlook blocked access to the following potentially unsafe attachments" error message when you send an e-mail message that contains a shortcut to a file in Outlook
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When you send a message that contains a shortcut to a file in Microsoft Outlook, the recipient may receive the following error message in the "Info" box of the e-mail message:
Outlook blocked access to the following potentially unsafe attachments:
Alternatively, the recipient may not receive any message, and the attachment is unavailable.
Note This behavior occurs when you right-click the original file, drag the file to the Inbox folder in Outlook, and then click Send with Shortcut.
This behavior is by design. When you create a shortcut by using this method, a .lnk file is not created. Shortcuts are recognized as linked files by the program. Shortcuts are considered to be a Level 1 file attachment and potentially harmful.
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.
To work around this behavior and to share files, post the files to a secure network share. In your e-mail message, you can include a link to the share to which you have given the recipient access.
Outlook blocks access to this kind of attachment so that the recipient is unable to open it. However, if you drag an existing shortcut for the same kind of file into a message and then send the file, the recipient may be able to open the file.
Note The option to send the shortcut by using this drag-and-drop method is unavailable.
Microsoft has classified dozens of file types as being Level 1 security risks. These file types include files that have .mdb, .mde, .ade, or .adp extensions.