>Hi,
>
>I have posted a message some time ago describing a problem a custom has where when more than one person loads the application, both suffer very slow performance. That is, when user A is in the program everything works fast. As soon as user B loads the application from another computer both users suffer great deal of slowness in getting the data or any file in the application folder on the server drive (be it .EXE, or any other).
>
>Working with the customer network engineer we pin-pointed the problem to the following:
>
>When a user A loads the application and this user is connected to network switch 1 and then user B loads the application connected to switch 2, no problem. The problem is only when both users use the same switch. The engineer confirmed it with two of his network switches. One is Cisco 3560 and the other is Cisco 3750. We ruled out that both switches could be diffective. And I am thinking, is there a configuration or some setting on the switch that has to be set to a certain value?
>
>Any help would be greatly appreciated.

Working with factory defaults, the switches should not require any special configuration. Is anything special configured on those switches? A show run on the switch should show any special configuration commands. If the network specialists believe that the switch was not specifically configured for supporting any advanced technology, you might just erase the configuration to factory defaults. Don't try the following if the switch does, indeed, need some advanced configuration. The common procedure to reset the switch to factory defaults is

erase startup-config
delete vlan.dat
reload

Well, that is what I learned on a Cisco Catalyst 2950; the details may vary depending on the switch platform.

Other than that, the problem might not be with the switches, but with connecting cables. For example, the application uses a lot of bandwidth. The individual workstations use separate cabling, but the connection to the server is shared. This would only be a problem if the application uses a lot of bandwidth.

Antivirus software often causes slowness. Although in this particular case the symptoms seem to contradict this hypothesis, you might still try to temporarily deactivate antivirus software, and see if there is a performance difference. If the antivirus software is, indeed, the culprit, you can tell it not to scan files with certain extensions - especially DBF, FPT, CDX.