I have several photos on the camera that are not on the memory card. How do I access these?

You may be able to get the images from the card. try using a program called BadCopy Pro. I used it a few times to get back images from memory cards that would not work on any computer. Good Luck.

Remove the memory card to access the photos in the internal memory. Alternatively, you can use the Copy command in the Playback menu to copy the photos from the internal memory to the memory card.

ALTERNATE WAY TO TRANSFER PHOTOS TO COMPUTER
If your photos are stored on the memory card, then remove the memory card from the camera and insert it into an USB memory card reader. Connect this USB memory card reader and memory card into the USB port of your working computer. Your computer will see this as an USB Mass Storage Device or an external storage device; you can then open the folder on the memory card and copy the photos to your computer. Memory card reader is a handy device and is inexpensive. You can copy photos from other cameras and you can also download photos off your memory card to someone else's computer without the need of installing any programs.

Take no more pics until you've recovered your photos, take the card out of the camera. This is to reduce the chance of you overwriting some of your "lost" photos. There are many good freeware photo recovery software options that may help you recover your photos. This article reviews and outlines several of the better ones.
Here's a YouTube video of your freeware options:

i have the same problem

It may have to be unlocked in the camera settings. My phone has a lock feature for photos, to prevent accidenta erasing.

Did you use the camera to format the card before you shot any pictures. If not, the camera can't use the card and used its own memory to store the photos. Use the camera to format the card, then the camera can continue to shoot more photos and store them on the card. When you download them to the computer, remember to get the one from the camera too.

You may try some photo recovery software to rescue the files on your digital camera sd card, here are some for your options.

Photo Recovery (for Windows)
Photo Recovery for Mac

Be careful: Before your pictures are recovered, do not attempt to save more files to the card in case the original files(your pictures) are overwritten.

there might some software trouble check using different memory card if nothing works try formating memory card r reinstall the software in camera

When viewing pictures, select the 'Menu' option. Scroll down and on the second page there's a 'copy' function that can either transfer photos from internal memory to a memory card or vice versa.

I didn't know this was possible until today, either. Handy!