My Ricoh 3500 color printer no longer is printing in color--just greys. It does not seem to be a problem with the color cartridges. Also, it streaks from left to right across a page from light to lighter (grey to light grey) when I do print. Any suggestions? I use an iMac g5 computer (new).

The streaking could be anything internal to the printer, such as the transfer belt or a drum unit. As for the lack of color, that sounds like it is a setting in the print driver that got changed from printing in color to printing in monochrome or grayscale. Look through your print driver settings to see if you can locate this setting and change it back to color. Also, once you print in color again you may notice that the streaking is a specific color, which will help to troubleshoot that issue.