Data transfer rate very slow

hi all

i use internet at my office though the download speed is very good but when i try to transfer data from my workstation onto my external HDD or USB drive the speed that i get is just 30kbps to 150 kbps (max). It takes 5 mins to download a 1GB file from the internet but takes ages to transfer it to my usb or hdd. What can i do to increase the speeds??

I can not ask my admin to do it for me.. haha

please help..

Thanks in advance