Please tell me how to solve the "memory card error" problem

Despite formatting my 1 GB memory card supplied with Canon Ixus 70 I am not able to take pictures. I am very fond of the camera and am frustrated to see this problem constantly. I request you to give me a solution for this.

Here are a few things to try:
1. When formatting the card, always format in the camera and not in the computer.
2. Reset the camera by removing the battery for several minutes or else reading the manual under "reset" or "initialize" for the correct procedure for your particular model.
3. Use a card reader to download the images to your computer (instead of the USB cord that came with the camera).
4. Check the canon website for any firmware updates for your camera.
Good luck and let me know how it works out for you.

Thanks for the reply. Still the problem is not solved. Will it be safe to reset the camera? I have checked with the manual and could not find how to reset the camera. any other solutions? pl. let me know.

Resetting the camera is always safe since all it does is put all the memory cells (not including the images) back to their factory settings. That way anything which somehow was changed and caused problems will be returned to just like it was when it was new.
I will look for other solutions and maybe another "expert" will drop by and offer some help also.