Hi Jun Ma,
Thanks for responding.
After restarting the BO server, Database servers, PC's, checking recent installations and updates, as well as trying multiple versions of both 32bit and 64bit JRE versions, the best we were able to find out was that the older versions of Google Chrome (GC) worked just fine, only the latest version causes the issue. It appears GC auto-updates unless you turn it off on the machine (No neat way to disable it for everyone across the network). We have subsequently decided not to use GC and stick with Internet Explorer. This works here but I understand it may not suit everywhere. We have not had any further issues using IE.
We still have the problem when used by GC.
Regards
Rod.