what's the best corporate antivirus software

I'd go for Symantec Endpoint Protection.
http://www.symantec.com/endpoint/

You set up a local SEP server, that controls all clients, gives you alert, reports etc. for connected clients.
You can manage all clients, disabling user control over the antivirus - which is propably one of the most important features.
If you set up your domain correctly - you can run a logon-script that automatically installs SEP on the client - so no one can connect to your network WITHOUT SEP.

All in all a great solution - we use it for our corp. network. 7 servers, +60 clients xp->Vista - works perfectly.

HTH,
Mark

Personally I've had bad experiences with Symantec and find McAfee a better solution

http://www.mcafee.com/uk/

trq dk - seems endpoint has various issues - see this link
https://www.experts-exchange.com/questions/23571852/Symantec-Endpoint-caused-endless-reboot.html?sfQueryTermInfo=1+endpoint+symantec

Hi _Pixelstone,

I had issues with Symantec hogging system resources. My company now uses Trend and it's a breeze to install and maintaine.

Cheers.

At our site it works perfectly on 7 servers and +60 clients at 3 locations. All managed from a online dashboard.

Hope your find the best solution for your needs.

//Mark

What about the AVG boys ?

All good points Thanks for your input ChiefIT

The second link doesn't work

Im backing trg_dk:.
We insatall symantec on all our clent networks. Thats about 20 business networks in total. Total of about 300 PCs. No  known issues here. I guess its a case of making sure you install it correctly.
The managmnet of this software is a breeze

Here is that link again: Sorry about the bumb link:
http://www.windowsecurity.com/news/WindowSecurity-Readers-Choice-Award-Antivirus-Kaspersky-Enterprise-Space-Security-Mar08.html

Thanks for all your help, Ihave not heard of NOD32 so I'll go and investigate it further and  also download the trendmicro trial software. Then I'll award some points.

Cheers

Thank you to all that posted comments