I agree with you 100%. Not sure of the Cat level. I have a feeling it is how the switches and hubs are set and how the cluster servers are configured. I think there are also many collisions. I am not a network expert but there are defitely issues. My outlook mail is also timing out on the mail servers most of the day.
Those Gigabit switches are not cheap...plus moving all the current PC's to a gigabit network card. Helpdesk would not be happy.

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