<span style="font-family: 'Verdana','sans-serif'; color: black; font-size: 9pt;"]Error 99 may not be with the lens. The 99 error code is a catch all code, so it does not give exact info about the problem. It can be poor contact between your body and lens, dust, etc. on the contacts or physical alignment issue, or a mirror problem, etc.<o></o>


<span style="font-family: 'Verdana','sans-serif'; color: black; font-size: 9pt;"]I had this problem and it was NOT the lens, but the camera body. There have been many posts across numerous forums about this error code, some very different depending on which camera model you have.<o></o>


<span style="font-family: 'Verdana','sans-serif'; color: black; font-size: 9pt;"]On the 1Ds3, the mirror&lsquo;s error 99 code problem will be fixed for free, plus there is a software update that makes the error codes more exact.<span style="mso-spacerun: yes;"] You need to make sure you have the latest software updates.<o></o>