Canon power shot sx 100 reads card locked

SD Memory cards have a tiny switch on the edge that marks the memory card as read only and prevents any writes. If you get the message "Card locked!" when you turn the camera on then turn the camera off, eject the SD card. With the card facing you (metal contacts facing away) the switch is on the left hand edge, slide towards the top of the card to make the card read/write again.

I had the same problem with my SX 100, and with a knife I gently bent in the metal tab that acts as the switch to read your card's "locked" status.  At first I tried to pull the tab out (into the memory card slot) more and that didn't help, so when I pushed the tab in (out of the way of the memory card slot) it did the trick.  I probably won't be able to use the "read only" feature on memory cards now, but I didn't use it anyway!  Now my camera works fine and can write to the SD card again!

Misterlink,
That was very helpful. I just fixed my camera using your method.
Thanks

We had this happen to us as well. It happened after we were trying out a new Pandigital digital frame. It seems that for some odd reason when you insert the card into the slot the frame pushes the card lock into the locked position. I'm not sure why this is necessary, since you can't write to the card or delete or rotate pictures while it's in the frame. We initally panicked since we had two cards and both were coming up Card Locked!. At first we thought the camera was broken and then when we realized both had been used in the frame we thought for sure the frame had corrupted the cards. Until we vistited this site we hadn't realized there was a lock on the cards. So thanks for the info.