cannot install the Sophos Antivirus home edition in Mac Pro 2008

WONDERFUL! 

I've tried all the suggestions and nothing works. Thanks for the response, RBaldry. Much appreciated. I'll wait untill the Feb 12 release.

I've now got 7.3 running on both my macs 15" MBP running 10.6.8, and 13" MBP running 10.7.2  Having been frustrated by this over the weekend, it seems that adapting the idea of olliedee worked.  I'm not exactly sure which services need to be shutdown, but I tried anything that looked like it would connect to the internet.  So I restarted the machine so there were no apps running, then opened activity monitor, and shutdown apple software update, iTunes helper, any scanner software, eye fi (wireless SD card software), adobe updater (using the quit process command), and anti-virus installed fine first time.  I think it's a bit of trial and error, but I got it to work on both machines.  As the guy from Sophos says it seems related to being able to authenticate to their SSL server, and it appears to be clashing with other software.  Anyway hope this helps other out.

RBaldry -

thank you very much for your response.  I believe you are spot on with the SSL conflict.  As the previous poster noted I did the following procedure and was able to install the product just fine. 

For reference I have no proxy set up or firewall.  I had open Safari, Photoshop, iTunes, and Mail open.  All of which connect to the internet or have an updater than connects to the internet. 

1.  Closed all open applications (mail, itunes, safari, photoshop)

2.  Opened the Activity Monitor utility

3.  Stopped the processes of a number of things like iTunes helper and some adobe app still running (*try anything that might connect to internet)

unfortunately for the sake of others I wasn't able to replicate it again by opening specific applications to find out which was the culprit.  Someone else may want to try installing Sophos with all the applications open that they have had and closing them one by one and trying again.  That way specific conflict applications could be identified. 

I don't think I really added anything from the previous poster but the fact that I had a number of applications open that definitely connect to the internet during all the attempts at installing Sophos. 

Again thank you to RBaldry for responding.  I think that users appreciate hearing that the company is frustrated with the problems as well. 

I don't know if it helped or not, But i shut down iTunes Helper and Sophos Antivirus home edition actually installed!

Woot!

You should be able to start iTunes Helper back up after the installation with no ill effects.

Ran into this problem and think I have found a solution. I downloaded the latest version of Sophos (8.0.5C...around 95 MB) a few times with the same result. Namely, the installer said it could not connect to Sophos. 

So I googled 'downloads sophos 7 for mac' and ended up at a Sophos site. When I started the download, I checked and found the file was about 85 MB. I'm not sure what version this was...perhaps an earlier version of Sophos 8.

It installed correctly and updated itself. The update was around 50 MB. 

All looks good at this point. Truly an irritating problem.