Realistically, your question can only be answered if you provide a great deal more information about your machine and network (if any).
Presuming that you are in fact running XP, there is one common issue that can be dealt with via a Registry setting.
Information is sent over the internet in the form of "packets".
These packets have a specific size.
Your machine's TCPIP Receive Window Size is handled by XP which does not "optimize" this feature.
Follow the below steps precisely to correct/optimize this feature:
TCP Receive Window size:
1. Launch window registry editor by clicking on
Start - Run
2. Click in the Open dropdown box and type in
regedit.exe then click OK .
3. Back up your registry by selecting File | Export type in a meaningful file name, in the export range section select All and save to your hard drive. To restore your old registry you simply import this file. (this is backup protection if you make any mistakes in this procedure)
4. Next you need to create a new registry key. On the left side you need to go to the directory HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
5. Select Edit | New | DWORD Value .
6. Rename the new registry key to TcpWindowSize.
7. Modify the registry setting for TcpWindowSize by double clicking on the key.
8. Change the Base Setting to Decimal.
9. Enter the value 64240 and click OK, then exit RegEdit.
10. For these settings to take effect you need to close all your open applications and reboot your system.
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Beyond that common tweak, you might benefit from visiting the Forums, here:
http://www.broadbandreports.com/forums/all
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And Check out the Tools here:
http://www.broadbandreports.com/tools
Particularly consider using
Doctor TCP
Best Regards