คำตอบที่ 39
code 99 ครับ... 
Canon DSLR Error 99 fix
Friday, April 29th, 2005
Please do not post a comment in this thread unless you have read this post fully including the updates and tried the various fixes listed. When you do post, please tell us the type of camera you have, the lens on at the time, whether you tried other lenses, etc. Read this before you post. Thank you.
Recently I started getting occasional errors when taking pictures with my Canon Digital Rebel (300D): error 99. Id have to reboot the camera by turning it off and then back on to get out of the error mode and in the process Id lose the last picture I took that produced the error dialog.
I searched around on the web in various Canon discussions and could not find anything definitive on this error. Some folks seemed to think it was a battery issue, some a card issue, some a lens compatibility issue. I was feeling pretty bummed out that my year old camera was showing signs of giving out. Then I called Canon Tech Support (should have done that first).
The guy at tech support listened and then told me that the lens contacts were dirty and to get a pencil with an eraser on the end, just a regular old pencil with a red rubber eraser. Detach the lens from the camera, hold it so that the lens gold contacts are pointing down and lightly erase their exposed surface, cleaning them of any hand oil that might have gotten on them.
Do the same thing with the gold contacts inside the camera body. This is a bit harder but its doable: just hold camera so lens opening points down so no gunk falls in. Erase lightly. I used a lens cloth and dabbed at the contacts rather than blow them so as not to blow the erasings inside the camera.
I did this to each of my three lenses just to be sure. Lo and behold, it worked (so far anyway). Ive shot numerous pictures with each lens and have not gotten a single error 99 message. One would think sites like dpreview.com would have this but I never found it there. Im psyched, I feel like I have a whole new camera now.
Update
If you are just discovering this thread and plan to post a comment about your error 99 experience Id appreciate if you could post:
1. Short description of what happened.
2. Type of Camera you were using: Canon 300D (Digital Rebel), 350D (Digital Rebel XT), 10D, 20D, 30D.
3. Lens on camera at time: Canon, Sigma, Tamron. Focal lengh, speed
Canon EF-S 18-55mm f/3.5-5.6
Canon EF 50mm f/1.4
Sigma 24-70mm F/2.8 EX DG
Tamron SP AF 28-75mm f/2.8 XR Di LD
Etc.
4. Did you try another lens too? If so which one?
5. What was the mode dial on the camera set to? Auto, P, Av, Tv, M, other?
6. How much charge was on the battery when it happened? How old is the battery?
7. Did you try any of the remedies in this thread: cleaning contacts, pulling battery, etc.?
8. What country you bought, live in, and use the camera in.
Thanks.
Update #2
One of our participants in the long comment thread below (Tom) got this in a message from Canon USA. It may help some of you isolate the problem before you post a comment/question.
To isolate the cause of the issue, we suggest that you do the following:
1. Turn off the camera.
2. Remove the lens, battery, and CF card.
3. Allow the camera to sit without power for approximately 20 minutes.
4. Insert a fully charged battery, and turn on the camera.
5. Depress the shutter button as you would to take a picture.
Does the ERR 99″ message appear? If it does, then the camera should be
serviced. If it does not, then please proceed to the next set of steps:
1. Turn off the camera.
2. Insert the CF card.
3. Turn on the camera.
4. Format the CF card in the camera.
5. Depress the shutter button as you would to take a picture.
Does the ERR 99″ message appear? If so, then the CF card is the most
likely source of the issue. Try using a different card.
If the message does not appear, please complete the following steps:
1. Turn off the camera.
2. Clean the lens contacts by gently rubbing them with a pencil eraser
or soft cloth. Be careful that you do not let any debris fall into the
camera body.
3. Reattach your lens.
4. Turn on the camera.
5. Depress the shutter button as you would to take a picture.
If the ERR 99″ message only appears when one particular lens is
attached, then that lens should be examined by a service technician.
If you see the ERR 99″ with a different Canon lens attached, then the
camera should be serviced.
http://www.richardsnotes.org/archives/2005/04/29/50mm-lens-contact-points/
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