Sophos failed to get free credentials and will not install unless I select no updates service

Question

Hello, 
 
 So I trying out the free Sophos AV software on Red Hat Linux system. The system in question is a standalone PC, running RHEL6.9. The only way I can get the software to install is to select no update support. If I select updates from Sophos (standalone PC) I get "failed to get free credentials". I do not have a server nor a proxy so there should not be any blocking issues that I am aware of. 
 
 Also the PC will operate off-line once it is approved to be used. Meaning there will be no network / internet connection to other systems. Media will only be transferred via CD. I would like to know how can I install update manually via downloads from Sophas website. If I can where may I find the definitions? 
 
 Thank you 
 huthrk@gmail.com

QC · Accepted Answer

Hello Robert Huth , 
 can't say what causes the failed to get free credentials but you can obtain and configure them manually . 
 There's no "delta" download you could fetch from the Sophos site as the whole package is checked for consistency and completeness. You'd have to download on a connected machine and then transfer its cache as update source to the off-line PC. Please see chapter 4 in the startup guide . 
 Christian