So, having recently bought my Digital Rebel XTi with Steph, I set out to talk with my friends that I know who are camera nuts. My friend Jordan had a Quantaray telephoto lens (70-210mm) that he could not get working. He believed that it was a problem with lens compatibility with his old camera. He said that if I could get it working with mine that I could have it. I put it on my camera and didn’t have any problems with it the first day. Today I got to Washington D.C. and started taking pictures. When I put on the telephoto lens, sure enough up popped Error 99. I fussed with it for awhile, trying to get it to line up in different ways, and eventually it would work only in the 190-210mm range. Steph and I stopped by a camera store and asked about the problem. The manager at the store said that the electric contacts on the lens are probably dirty, and to clean it with denatured alcohol. When I got to a computer, I looked it up and found this solution on Richard’s blog. I cleaned the lens contacts with an eraser, and it seems to be functioning properly now. Back to D.C. tomorrow for some more field testing though!Pics soon!Quantaray-CN AF1.4-5.6 70~210mmFull BatteryEmpty CF card