Problem Description

Sophos Enterprise Console version 4.5.1
Installed on Windows 2003 (but this is not important)
Trying to deploy Sophos 9.5 to a Windows 2008 r2 Server.

When trying to deploy Sophos 9.5 to a Windows 2008 r2 server from the Enterprise console, we received the following error.

80070520 “Could not start installation program on the computer: A specified logon session does not exist. It may already have been terminated”

Answer (well sort of)

After speaking to Sophos for the first time they told me to follow these instructions.

http://www.sophos.com/support/knowledgebase/article/62730.html

At the time of writing the video in the link above has inacurate information. I followed the instructions but it still did not work. I contacted Sophos again and they suggested I make a change to Group Policy.

Computer Configuration | Windows Settings | Security Settings | Local Polices | Security Options
you will then see one of the following two items.

Network Access: Do not allow storage of credentials or .NET passports for network authentication
Network Access: Do not allow storage of passwords and credentials for network authentication

Sophos suggest that you disable this.

Caution

Disabling the above does allow remote installation of Sophos from the Enterprise Console; however; this weakens your network from a security point of view and goes against the cis recommendations.

So beware, this solution works but has Security implications, if I find a better way of doing this I will update this article.