Windows 7, IE 8 and SharePoint - slow opening up Office files

Hello,

We have a GPO modelled after the Vista Computer GPO that was downloaded from Microsoft which has been active in our network for many years. We are just adding Windows 7 Enterprise into the infrastructure and these workstation take for ever to open files from our SharePoint WSS 07 v3.

When I take the GPO off the workstation, the system can access the file without any lag.

Does anyone know which setting(s) needs to be modifed to fix this issue?

Thanks in advance.