Windows clock - synchronisation

I have recently installed Kaspersky Internet Security v6 on two computers. A third has McAfee Internet Security operating. The programmes are working well. All three computers have Windows XP SP2 installed.

However, I have a small issue because I cannot get any of the computers to synchronise the windows clock. It does not matter which timeserver I select the results are always the same. I have made a number of attempts to synchronise over the last few days in case the timeservers were not functioning properly. However, this seems not to be the case.

Kaspersky’s technical support are baffled – they are getting the same results as myself and even get the same result when uninstalling their product during tests.

Please can anyone help?

Thank you