When I need the pop up flash on my EOS 7D, I get an "err 05" message. ???

Question

The camera doesn't flash and no photo is taken.  It tries to open the flash but it won't release.  

Answer 1

This is a fairly common problem on many Canon cameras.
Usually it's a simple fix related to the micro-switch under one of the leaf springs in the hot shoe, that's there to prevent the built-in flash from opening when something is mounted in the hot shoe. Usually it's just that the micro-switch's spring loaded, actuating "pin" isn't returning fully and the camera "thinks" something is mounted in the shoe. More rarely it's dust or dirt that gets into the micro-switch and causes that pin to stick.
Go to this website and take a look at the eleventh photo (counting down from the top of the page). That shows the little "button" of the micro-switch under the leaf spring, that's the top of the actuating pin. Other photos there address other problems (loose hot shoe, etc.) And the section with the eleventh image is actually showing how to replace the little pin in the micro-switch, should it be lost.
However the most common problem is simply that the pin isn't able to pop up fully for some reason. And often there is no need to disassemble the hot shoe at all, to correct the problem with the micro-switch. Once you have located the switch in your camera's hot shoe, simply use a precision screwdriver or wooden toothpick to "lift" the leaf spring slightly, to allow the micro-switch to pop back up all the way. Maybe tap on the top of the pin to "coax" it into springing back up fuly. This is frequently all that's needed. Sometimes you need to slide the tool toward the rear of the camera while it's under the leaf spring, to gently and slightly bend that spring so that it gives a little more room for the micro-switch pin to pop up.
If this doesn't work, there might be dust or dirt in that pin keeping it from springing back up fully. To clean that would mean some minor disassembly. (See other photos at that website.)
More rarely, there can be issues around the flash hinge area... dirt or just some lubrication needed so that the flash can properly open (usually when this is occuring the flash opens, but only partially).
Another thing that can happen, but rarely does, is the latch holding the flash closed doesn't fully release and prevents the flash from opening. It might have gotten bent during use or there may be dirt in the mechanism. Very rarely it actually fails and needs replacement. You can test if this is occuring after checking the micro-swicth and finding the flash still doesn't open properly. To test, make sure nothing is in the hot shoe and the camera is turned on, then press the "flash" button while using your fingernail to help coax the flash open. If it seems securely latched closed when doing this, there may be a problem with the latch itself.
If none of the above works, or perhaps you just don't feel comfortable fiddling around with things to try to fix yourself, send your camera in to Canon... Especially if it's still under warranty.
But, quite frankly, in my opinion the best and easiest solution is to just not use the built-in flash at all. One of my two 7Ds has a "stuck flash" that I've never bothered fixing. In twelve years using Canon cameras, most with built-in flashes, I can probably count the number of times I've used a built-in flash on one hand. In fact, I've accidentally pressed the flash release button and had the flash pop up unwanted or gotten ERR05 far, far more often than I've actually purposely tried to use any built-in flash. So I simply don't care if the built-in flash on my 7D works or not.
Why? Well for one thing the built-in flash is in just about the worst possible place to cause redeye and ugly shadows: just above and near the lens axis. It's also pretty anemic, not much good beyond 15 or 20 feet. And it much more rapidly drains the camera's battery(ies). And it is slower recycling. And if used for extended shooting, it can overheat and shut down (temporarily, to protect the flash from burning out). That will put an end to shooting while the flash cools down.
Finally, the 7D offers wireless off-camera flash control, that's handled by the built-in flash too. But I use an ST-E2 module instead, because it has more reach and uses near IR light (instead of white light flashes) to communicate with the flash.
And I use various Canon accessory flashes instead of the the built-in... They are considerably more powerful (some with reach upwards of 100 feet, even close to 200), can be put on a flash bracket (using an off-camera shoe cord) to much improve shadows and prevent or at least greatly reduce redeye, have their own batteries (and accessory battery packs) so they don't drain the camera's, recycle a lot faster, and are a bit less prone to overheating & shutting down with extensive use. If the accessory flash shuts down to prevent overheating, all I need to do to continue shooting is switch to a different flash.   
I even wish Canon would make an APS-C camera without any built-in flash. Personally I don't need it and a camera without one would be simpler, might prevent some issues (such as accidental pop-ups or ERR05), and I suspect would or could be better sealed against dust and moisture. I've used several Canon models without  (EOS-3, 5DII and others), as well as many other manufacturers' cameras that didn't have them, and never really missed built-in flashes.
Sure, it can be nice to have a built-in flash right at hand for an emergency... But that's why Canon makes 270EX and similar small flashes, IMO. Get one of these or the larger flashes (430EX, 580EX, 600EX-RT, etc.) and use it... Especially if you also use an off-camera shoe cord and flash bracket to position the flash off to the side and higher, and your flash images will be much nicer looking!
Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7D(x2), 50D(x3), some other cameras, various lenses & accessories
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