Why do my images get distorted on my Nikon DSLR?

Question

I have had my Nikon D40 for a while, and some of the pictures are coming out distorted. Two examples are below:
So my questions are:

1. How do I fix them after the fact? - i.e. after they have been imported from the camera - if possible
2. How do I prevent future pictures from being distorted like this?

Thanks
and

Asked by marcamillion

Answer

Likely culprits, in order of probability:

• Bad SD card (by far the most likely).
• Bad cable or card reader.
• Something horribly wrong with the camera's electronics.
• Something wrong on your computer.

The "bad card" scenario is, unfortunately, the most likely, and in that case the pictures are lost. If it is just the reader, transferring the files again might work — but you've probably already tried that. If you reformat the card, it might work fine, but I sure wouldn't trust it.
Bad cards are a fact of life... I buy only brand-name pro-level cards. They're more expensive (possibly exploitatively so) but I think the extra quality guarantee is worth it.

Answered by mattdm

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