I'm sorry about the issue. Was it working previously? Or is this the first time you are trying to download photos on a memory chip / card?
What's the model of your camera, if any?
What's the model of your Dell Inspiron Desktop, such as 3000, 3646, etc.? (Please check the label(s) on it.)
With the memory card inserted to the desktop, can you click on Start, then click on Computer, then open each drive letter there, except the C: drive, and see if there is the folder DCIM and/or any subfolder in it?
Please reply at the box below. Thank you.