By Pass tray printing

1. may be something is wrong with your printer. try it using on another PC.
2. if printer is working fine then reinstall your OS.

HP Officejet Pro L7780 Wireless All-in-One Color Printer

I would like to install a Samsung ML-1650 on a Mac Mini running OS X 10.4.11. So far I cannot find a driver or install program.

We have become aware of an incompatibility between the ZoomAlbum software and the Canon PIXMA printers listed below. This issue applies only when using the ZoomAlbum software to print Photo Album covers with Mac OS X.
Affected Models
PIXMA MP240, MP250, MP480, MP490, MP560, MP620, MP640, MP980, MP990, MX320, MX330, MX860, iP3600, iP4600, iP4700 Printers
Phenomenon
The affected PIXMA printers are designed to feed paper via the rear tray with a center-feed mechanism and two paper guides. However, the ZoomAlbum software was intended to feed paper from the rear tray in printers with a right-feed mechanism and a single paper guide. As a result, when using the ZoomAlbum software with Mac OS X to print Photo Album covers with the affected Canon PIXMA printers, the printed image may shift.
Countermeasure
To remedy this problem, please use the following settings when printing Photo Album covers with Mac OS X:
1. Click System Preferences
2. Click Print & Fax
3. Select your Canon PIXMA printer as the default printer
4. Select DL Envelope for Default Paper Size in Page Setup
Note: Be sure to change the Default Paper Size back to Letter after printing the cover.

Hi
Click on the following Link for the MAC Drivers

Click on DRIVERS MAC 10.5

http://support.lexmark.com/index?segment=DOWNLOAD&userlocale=EN_US&locale=en&productCode=LEXMARK_C500N&page=recommendedDownloads#1

It sounds like the driver provided by the manufacturer may have a glitch in it. I would recommend sharing the printer to the MAC:

Add the Shared Printer to Your Mac Launch System Preferences by clicking its icon in the Dock.

Click the ‘Print & Fax’ icon in the System Preferences window.

The Print & Fax window will display a list of currently configured printers and faxes that your Mac can use.

Click the plus (+) sign, located just below the list of installed printers.

The printer browser window will appear.

Click the ‘Windows’ toolbar icon.

Click the workgroup name in the first column of the three-pane printer browser window.

Click the computer name of the Windows machine that has the shared printer connected to it.

You may be asked to enter a user name and password for the computer you selected in the step above.

Select the printer you configured for sharing from the list of printers in the third column of the three-pane window.

From the Print Using dropdown menu, select the driver that the printer needs. The Generic PostScript Printer driver will work for almost all PostScript printers, but if you have a specific driver for the printer, click ‘Select a driver to use’ in the dropdown menu, and select the driver.

Click the ‘Add’ button.

Use the Default Printer dropdown menu to set the printer you want to use most often. The Print & Fax preferences pane tends to set the most recently added printer as the default, but you can easily change that by selecting a different printer.

What machine are you using?

did you install the latest printer driver for the MAC?
the following link have the latest driver.
http://downloads.lexmark.com/perl/downloads/downloads.cgi

discontinue use of automatic installation.
use manual installation. meaning go to printer and configure the communication port 1 and install the driver by selecting the correct printer.

check your mac connection settings, change if needed, try install new printer.

1. Manually adjust color from the driver (Mac OS 9) 2. Manually adjust color from the driver (Mac OS X) 3. Manually adjust color from the driver (Windows) 4. Confirm that the recommended ink tanks are installed properly (iP1500 / iP2000) 5. Disable Monochrome Effects in the printer driver (Windows) 6. Perform print head alignment (Mac OS 9) iP1500 / iP2000 7. Perform print head alignment (Mac OS X) iP1500 / iP2000 8. Perform print head alignment (Windows) iP1500 / iP2000 9. Perform print head cleaning (Mac OS 9) iP1500 / iP2000 10. Perform print head cleaning (Mac OS X) iP1500 / iP2000

http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=SupportDetailTabAct&fcategoryid=257&modelid=10236