An end user in an environment protected by Symantec Messaging Gateway (SMG) sends a message. The recipient of the message navigates to securemail1.messagelabs.com and succeeds in logging in and viewing the message. However, when the recipient attempts to download one or more attachments, they receive a .partial file.
This behavior is most frequently seen when the recipient attempts to download an attachment from the securemail1 portal with Internet Explorer 11 in Compatibility mode, or a legacy version of Internet Explorer.