I Have Powershot 85 when i turn the camera on the lens extends but there is no picture in the view finder recall

SOURCE: Canon 40D LCD Wont come on buSY flashes in view finder

Okay, this is simple. Your camera can take several pictures at one time in a burst. However when you release the shutter button your processor takes a second to actually SAVE the pictures to the card in the camera. One thing than has helped me in my wedding photography business is to buy the fastest speed cards I can find. It significantly reduced my "busy" time.

SOURCE: no picture in view finder before I take picture

If it is Canon A60 camera then it has bad ccd imager and requires replacement.
Canon replace ccd imager Free of Cost as per announced scheme.
Please click Canon CCD Imager Advisory for details.

If camera model is different then check is it listed in above Canon page for free repair.

SOURCE: Canon A720is turns on, but lens will not extend

I had the exact same problem. Since my camera is out of warranty, I decided to try to fix it myself; figuring the cost of repairing it would be close to the cost of a new, better camera. If yours is still under warranty, let Canon fix it for the cost of shipping.

I unscrewed all of the screws and carefully pried open the back of the camera. Part of it will come apart easily, but for the part that wouldn't, I slid a razorblade into the crack between the pieces and used it to separate the pieces.

I was shocked by what I found. The "mechanism" for switching between picture and review mode, appears to consist of a tiny black piece of something (doesn't look like metal, but I assume it's conductive). The physical switch that you operate on the back of the camera, appears to push this away from the circuit board. When that happens, the camera goes into review mode.

I assume that over time, this flimsy piece of whatever begins to wear out and eventually won't return to the circuit board. I slipped a small screwdriver under this piece and bent it back towards the circuit board.

That did the trick, The camera now functions as it's supposed to with one exception. Now, when I go into review mode, the lens won't retract (although it will when I power the camera down). Personally, I'm fine with that, because the lens going in and out is a huge waste of battery.

One thing I learned from this is that when you leave your camera inactive for long periods of time, make sure it's in picture mode, as this should reduce the strain on the flexible "switch".

SOURCE: lens error restart camera SD750

somebody saying under warranty

http://www.digitalcamera-hq.com/digital-cameras/canon-powershot-a570is_question.html?qid=12688

SOURCE: Canon PowerShot SX100 IS Lens Stuck

If the lens does not extend/retract when the camera is powered on, then lens assembly is damaged.

Unfortunately, such Canon SX100 (and the SX110 too) has a very fragile lens assembly, and it's damaged very easily. Most of the times the internal gears, the plastic post guides and the motor are damaged at the same time, so the only solution is to replace the whole lens assembly.

The lens replacement requires a qualified camera repair technician, unless you want to try in repair it yourself, which requires tools (scredrivers, soldering iron, desoldering tool, magnifier glass with light, etc).

Best regards,