Thanks for taking time to reply to this post everyone. It was a relief to learn it might be possible to retrieve lost images from the CF card. I looked at the sites mentioned in your responses as well as calling a local camera shop for advice.

For Richard: I did put the card back in the camera to check for photos. The "No Image" message came up each time I tried it. The cable I ended up trying to use was still in its original packaging and should have been trouble free, but it was after using it that the images disappeared.

My final approach was to take it to the camera shop since I didn't want to risk making a mistake. If I'd only had my usual assortment of random photos on the card, I might have been tempted to try to fix it. Everything on the card was from a Pet Portrait fundraiser, RAW files shot yesterday. People had paid in advance for photos which, so far, I'm not able to provide. I hope the camera shop comes through. They quoted $70 to do the repair until they noticed that the card has free manufacturer repair warranty. At this point, there was nothing to lose by going that route, and I have learned that there are recovery systems out there for all kinds of technical issues.

Thanks again for the great advice. I should know Friday or Saturday whether I'll have photos to edit. Keep your fingers crossed.

History: I took a lot of shots with my Canon 7D and filled the CF card yesterday. I deleted what I didn't want and continued to shoot without filling the card. When I got home, I reviewed the images in the camera and deleted more that I didn't want because they were either redundant or out of focus. When I was ready to upload to the computer (MacBook 2014), I put the CF card in a "Sunpak" card reader and plugged into a USB port before following my usual steps which were: open Elements 13 Organizer, click "Import", click "from Camera or Card Reader." At this point, I kept getting <None Detected> no device found. I plugged the card reader into the other USB port and followed the same steps and got the same result. As an alternative, I put the card back in the camera and plugged the camera in with the USB cable. I still wasn't able to use the Elements 13 download, but the connection started working in another window that showed the computer was processing in excess of 33,000 images! I doubted neither the CF card nor the computer disk has room for that many, so I pushed "stop" to close down the import (or whatever it was doing) in that section. The new photos weren't included in that operation as far as I know, and none of the old photos that came through before I stopped the process appeared to be on the computer unless they're double images in the photo section.

The main problem: The CF card no longer has any images on it. I didn't think I told the computer to delete anything (I usually do that in the camera by reformatting when I'm sure everything has transferred to the computer). Obviously I did something horribly wrong.

Any ideas what I did to delete the card? Did closing the download by hitting "stop" erase the card? Would it be possible to find the images that seem to be lost or are they truly gone forever? If the images are to be found, where should I look (I believe I've looked at all of the files on the computer). I should mention that the computer iPhone and tablet are linked to some degree and appear to trade photos. The shots I took yesterday are not on the other devices.

If you never plugged your camera directly into your computer before, it probably started up one of the Canon programs (such as ImageBrowser) by default, which then started to compile a catalog of ALL the images on your computer.... hence the 33,000 images.

I doubt there is anything wrong with your memory card or that the images are actually lost.

It is not a good idea to delete images from a memory card unless absolutely necessary (i.e., running out of space and don't have extra cards). It is too easy to accidentally delete the better image or more than one image... and may even be possible to corrupt the memory card.

Best to download all your images to your computer, then use the larger monitor screen to sort through and delete the ones you don't want. That's much better/safer than trying to do it in-camera or with camera tethered.

I'd suggest you turn off ALL the "auto download" features you have set up on you computer, ESPECIALLY those in Lightroom or Elements.

Instead, use your computer operating system:

1. Before you even insert the memory card, set up a folder to receive the new images (however you organize your images... that's up to you).

2. Insert card in reader. If anything automatically tries to download the images, cancel it.

3. Navigate to and open the card in your computers OS... such as Windows Explorer or whatever Macs use now (I haven't used a Mac in about 20 years).

NOTE:I t's possible to set up your computer to do this by default, any time a memory card is detected.

4. Look for a folder on the memory card called "DCIM" and click on that (ignore the "MISC" folder you'll also see).

5. Look for a folder named something like "100EOS7D" and click on that (ignore the "EOSMISC" folder). You should now see a list of all the images.

NOTE: There may be more than one folder: "101EOS7D", "102EOS7D", etc. The camera automatically creates add'l folders when the file numbering system requires it. Be sure to check inside and copy from each, if there are multiples.

6. Highlight all the images (click on one to highlight it and then use "Ctrl A" to highlight all the rest). Then drag and drop them to the folder you created.

NOTE: In Windows, drag and drop using the mouse's left click button will automatically "copy" images.... while drag and drop with right click will bring up a menu giving choices... in either case, always "copy".... don't "move" images. Moving them removes them from the memory card and you don't want to do that yet. Copy leaves the original on the card, just in case there's a problem with copying them to your computer.

7. Let the system complete copying the images, then point Elements organizer to the images and tell it to import them (or however that's done in Elements... I use Lightroom and am using that terminology, but I imagine Elements is similar).

8. Once you confirm the images have been safely copied to your computer and have backed them up in whatever manner you use, it's safe to delete the ones on your memory card. I recommend you do that by using "format" in your camera (ONLY in the camera where the card will again be used... NEVER format in your computer or in another camera... this "prepares" the card for use in that particular camera). Personally I usually don't format my memory cards until I go to use them again.... The first thing I do whenever I swap a card into my camera during a shoot is "review" one image to be certain they are images that have already been copied off the card.... then when I'm sure, I format the card (some cameras... not sure about 7D... can do a "deep format" which takes longer. That's usually unnecessary... a quick "normal" formatting suffices).

Formatting in-camera doesn't really erase images. Instead it marks them as "okay to over-write". If you accidentally format, all is not lost. The images are still recoverable until you start using the card and sending new images to it. (Even then, it may be possible to recover images that haven't been over-written yet.)

All this takes far longer to write and read than it takes to actually do it. Using the OS data transfer method described soon becomes second nature and is pretty foolproof. There are just too many ways that "auto downloads" can screw up or be set incorrectly. I don't trust them!

Note: If you shoot JPEGs, you can see small thumbnails of them in Windows Explorer and can enlarge and view them in Windows Picture Viewer. But if you shoot RAW (CR2 in your case), those are not directly viewable, will appear with a "generic" icon on lists. HOWEVER, there are "codecs" you can install that make possible viewing thumbnails and even enlarging RAW files (unfinished, so color, contrast, etc. will be off... but useful to check focus, composition, etc.) At one time Canon had a codec they offered for free. I used it for a while on an old computer, but when I went to a 64bit operating system, it would no longer work and Canon didn't seem to have any interest in updating it. I've heard there are some other codecs available free from Microsoft and elsewhere, but AFAIK they are fairly restricted in what they can handle and I have no idea how well they work or if any of them are able to deal with Canon CR2 files.

I use a codec called FastPictureViewer. It costs all of $10 and allows almost every known type of RAW file to be previewed right in Windows, without having to open Elements, Lightroom, Photoshop, etc. It also allows direct viewing of TIFF, PSD and some other image file types that Windows can't normally "see". It has worked great with every type of RAW file (and others) that I've thwon at it and is well worth the money, IMO. I use it on three computers. https://www.fastpictureviewer.com/codecs/

P.S. If you need image recovery software, send me a PM. I have a bunch of licenses for Lexar Image Rescue that came free with memory cards I've bought over the years. Normally it costs about $50 for Image Rescue, but all you need to activate it is the license number (after downloading and installing from http://www.lexar.com/support/downloads/). I have used it and it works. I only need one copy, so am happy to share some of the 8 or 10 extras I got for free!

In future I suggest you have extra cards so you don't have to do that in camera delete stuff, as stated on those tiny little screens it is easy to misread or select the wrong command.

I did once accidentally erase a CF card before I had downloaded all the images. I used an image recovery program I bought on sale a few years ago "just in case". It found a couple of thousand images, some as old as 4 years. Of course a fair % were not complete or downloadable but the ones I wanted were all there being the latest. Strangely enough some of the oldest were also recoverable because they were from when I was first learning to use my 7DII and had been doing up to 1000+ images a day doing bursts of water birds and so were in parts of the card's memory that I never wrote images to since then.

History: I took a lot of shots with my Canon 7D and filled the CF card yesterday. I deleted what I didn't want and continued to shoot without filling the card. When I got home, I reviewed the images in the camera and deleted more that I didn't want because they were either redundant or out of focus. When I was ready to upload to the computer (MacBook 2014), I put the CF card in a "Sunpak" card reader and plugged into a USB port before following my usual steps which were: open Elements 13 Organizer, click "Import", click "from Camera or Card Reader." At this point, I kept getting <None Detected> no device found. I plugged the card reader into the other USB port and followed the same steps and got the same result. As an alternative, I put the card back in the camera and plugged the camera in with the USB cable. I still wasn't able to use the Elements 13 download, but the connection started working in another window that showed the computer was processing in excess of 33,000 images! I doubted neither the CF card nor the computer disk has room for that many, so I pushed "stop" to close down the import (or whatever it was doing) in that section. The new photos weren't included in that operation as far as I know, and none of the old photos that came through before I stopped the process appeared to be on the computer unless they're double images in the photo section.

The main problem: The CF card no longer has any images on it. I didn't think I told the computer to delete anything (I usually do that in the camera by reformatting when I'm sure everything has transferred to the computer). Obviously I did something horribly wrong.

Any ideas what I did to delete the card? Did closing the download by hitting "stop" erase the card? Would it be possible to find the images that seem to be lost or are they truly gone forever? If the images are to be found, where should I look (I believe I've looked at all of the files on the computer). I should mention that the computer iPhone and tablet are linked to some degree and appear to trade photos. The shots I took yesterday are not on the other devices.