How to tell if Camera or CF card has problem?

Camera=Nikon 5400 Card= Compact Flash
Take pics, can view them with card in camera.
Using patch cord to usb in computer, says device is malfunctioning. Patch cord is new
Take card out, both Kinko's and Walgreen's card readers say files corrupted
Cheapest CF card is at best buy for $29
Question is:
Can I assume the card is the problem, even though the camera can read it?

Even though I love my Nikon 5400 with its manual options, even the cheapest digital cameras have
way more MPs, and would probably work for me. And I can't afford the camera I would like to have
(actually right now I can't afford any camera)

Two solutions. One, very simple, buy a new CF card. Second try a usb card reader. Readers aren't expensive and are available where ever cameras are.

Barring these two, perhaps your camera really does have a problem. Impossible for us to tell from here.

Yes, card has a problem even if the card can read it. You should replace the card right away.

Before using the new card, format it first in the camera.CF cards are still available in stores.

http://keerok-photography.blogspot.com/2011/05/how-to-keep-your-memory-card-healthy.html

When was the last time you formatted your CF card? Can't remember?
Have you made a habit of reformatting your CF card everytime AFTER you transfer all files (from the card) to your computer? If not, then that could be the reason why you are having a problem now.

Formatting deletes All files from the card and keeps the card's file system in good order and prevents errors.

If a format doesn't help… You may need to think about buying a new card. But, make sure you format it before you use it the very first time and reformat it after every file transferral to your pc.

p.s. The format function can be found in your camera Menu.