Hope this link applies -> http://forums.cnet.com/5208-12546_102-0.html?forumID=133&threadID=238817&messageID=2950937&tag=forums06;posts#2950937
We also check the BIOS to see if the USB ports are enabled.
You supplied the make and model but no OS, no story so we'll start with answers that might fit.
I have a DELL Inspiron 9200 Laptop.It has 6 USB ports and all of them are not working. What can be done?