Interesting...I have not been able to put a card in backward.
And I have tried many times (by accident of course).

I guess if you did get it in backward, it could have some negative results.

If you have photos on the card ... take the card to your local photo processor and see if they can save them to a CD (about $2).

If that does not work, you will need a card reader for your computer.
($10 to $20 at any store that sells digital cameras).

See if you can read the card with the card reader (on the computer).
If you can see the image files you should be able to download them to the computer.

If that does not work, you will need special software.
Go to Google.com and search for
"memory card recovery"
That will give you a long list of software to try.
Some is shareware, some is free, some you pay for.

After you get the pictures off the card,
use the computer to delete every file and folder on the memory card.
Do NOT format the card with the computer.

That will usually fix the card so that it will be recognized by the camera.
Then before you take any photos, use the camera to format the card.

You should be good to go.

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