No Power The camera has been sitting idle for about two years in an air conditioned office- no batteries but CF card installed. It will not power up from batteries or AC adapter. There was slight corrosion on the battery contacts that was cleaned with a cloth and pencil eraser: No Luck. Battery compartment was then sprayed with WD40: still NL. I also have a Vivitar ViviCam 3735 with an identical history and symptoms, except it will power up with the AC adapter. The CF card fits both and works fine.

No, usually you'll just get a warning that the card is missing but the camera should power on.

Hi,

I believe this post will help you out..
Please CLICK HERE

Replace the cf card.

1.Remove the battery, lens and CF card. Allow the camera to sit without power for 20 minutes and then reinsert a fully charged battery.
2.Turn the camera on and push the shutter button as if you were taking a picture.
3. If you don't get the error message reattach the lens and insert the CF card.
4. Check the below canon eos 20d service manual link:
http://goo.gl/YtVLQR

it will help you to save a lot of money
Hope it helps, Thanks

1.Remove the battery, lens and CF card. Allow the camera to sit without power for 20 minutes and then reinsert a fully charged battery.
2.Turn the camera on and push the shutter button as if you were taking a picture.
3. If you don't get the error message reattach the lens and insert the CF card.
4. Check the below canon eos 400d service manual link:
http://goo.gl/LHYVAy

it will help you to save a lot of money
Hope it helps, Thanks

.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.

To fix this err99 issue, 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.
If it appears again, then proceed to next steps 1. Turn off the camera. 2. Insert the CF card. 3. Turn on the camera. 4. Format the CF card in the camera.
If you still get the error you should send your product to canon for servicing.

This is something I found when googling your problem.

Thank you for contacting Canon product support. I'm sorry to hear that
your EOS 10D is displaying an "ERR 99" message.

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.

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.

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.

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.

Change out the CR2016 3V battery. You have to remove the rechargeable battery to get to the CR2016. Refer to the manual for proper instructions.

Had the same issue with a two year old camera. This solved my problem.

Perform the following procedures if your camera does not detect a CF card. 1. Restart your camera. - Set the camera's power switch to and remove the batteries. - Open the CF card slot cover to make sure the CF card is securely set in the card slot. - Insert the batteries and turn the power switch . 2. Format a CF card. Format the CF card with your camera. Refer to the Camera User Guide supplied with your camera for instructions on formatting your card. 3. Check if your camera detects other CF cards (If you own multiple CF cards.) If your camera does not detect a CF card after performing the procedures 1 and 2 above, the card that wasn't detected may have a defect.