When I plug my Panasonic DMC-TZ3 camera into the USB port on my Dell Latitude E5500 laptop computer, the computer is not finding the hardware. This has worked fine for years, and stopped working soon after I backed up my hard drive onto a Maxtor external hard drive. I know I could download the pictures by just connecting the data card, but I'd like to keep doing it the way I have before. Any way to fix this?

Do any of the USB ports work with other devices?

If no, RMB click on "My Computer" guessing you have windows, from the drop down menu, LMB "Manage" LMB Device manager and check in the window to see if there's a yellow question mark by any of the devices. If so, you need to re-install the driver for that device, possibly this will include your USB drivers.

You should find the drivers you need either on a disk supplied by DELL or go to their web site, follow links to support / downloads, entering your PC model details as you go. You should find your way to drivers to download. While you're there, download all and save to disk, just in case you re-install your system again.

If other devices do work, there's some sort of conflict going on. the easiest way around this is to buy a universal card reader, a small box which reads all kinds of cards and connects to your PC via USB.