There are many sites around the internet complaining about Canon's poor design and workmanship being responsible for the dreaded "E18 Lens Error" problem. This isn't going to be one of them.
First, a little basic, general information. Digital cameras are complex mechanical and electronic machines.
Unlike your average cell phone, they are not built to be dropped or abused. Because they are similar in size to cell phones, many people think that they can drop their digital cameras "only a few feet" and they will keep working just like their phones. Believe me, I have dropped my cell phone MANY times and haven't had the first problem with it. I've even had the entire casing pop off and simply snapped it back on.
Digital cameras, however, contain many moving parts and switches that must work in proper synchronization in order for the camera to function. And we're talking about some pretty tiny gears and switches, many smaller than the size of the end of a pencil eraser. One good whack and the alignment between the gears, zoom barrels, and switches gets messed up. Because the lens is protruding from the front of the camera, that is the most likely area to hit the ground first. Kind of like dropping a piece of buttered bread, it always seems to land butter-side down!
Here's where the Canon E18 error comes in. Canon, in order to give the consumer a little information as to why their camera is malfunctioning, decided to display the "E18 Lens Error" code on the LCD of their cameras when they malfunction. That was their mistake. Any damage to the zoom gears or motor, or mis-alignment of the zoom barrels, or problem with the switches or sensors in the lens will display the error code.
Most manufacturers design their cameras to simply power back down when an error occurs, rather than designate the specific problem. That way, people won't complain that those cameras have faulty lens designs. Canon probably should have done the same thing. Even our cars now just have one "Check Engine" light to warn of a bunch of different possible malfunctions.
In the literally thousands of digital cameras we have repaired here, fewer than 1% of those cameras have had lens malfunctions that could be attributed to poor design or manufacturer defects. The other 99% have suffered from impact, water, or sand damage.
If the camera makers wanted to make cameras that were impact resistant they would have to make them a lot bigger than what they are now, which people don't want, or make them more expensive.
If you want a camera that is impact resistant, waterproof, freezeproof, and dustproof, you might check out the Olympus SW series of digital cameras. The Olympus Stylus 1030 SW may be the camera for you. Be prepared to spend almost double what you would spend on a comparable "normal" camera!