QHennepin County Library now has eBook lending services for Sony and Nook eReaders, but not for my Kindle. Why is this? Is there any way we Kindle owners can participate in their program?

WILLIAM RICKMAN, EDINA

AFor technical reasons, you're locked out of the Hennepin County Library's eBook program for now. Its eBooks aren't compatible with the Amazon Kindle's DRM (digital rights management) software, which prevents unauthorized copying of eBooks. (Similar software was used by online music stores to copy-protect songs, but its use for music has diminished.)

The library uses DRM software from Adobe Systems, which is compatible with three types of eBook readers, the Sony Reader, the Barnes & Noble Nook and the Kobo eReader. The Kindle uses different DRM software from Amazon.

But the library does have plans to offer eBooks on more devices.

Although it will require new software that's still in development, the library plans to make eBooks available for downloading to the Apple iPhone and to smart phones that use the Google Android operating system.

Eventually, the eBooks may be available on the Apple iPad as well.

For more information, see the Hennepin County Library's "Downloadable eBooks FAQ" at tinyurl.com/24nnagg.

Q I have a Hewlett-Packard Photosmart C6280 All-in-One color printer. I've set the printer's ink setting to "Print in Grayscale - Black Print Cartridge Only," so in theory I shouldn't be using the printer's colored ink at all.

However, the colored ink depletes and needs replacing often. I e-mailed the help desk at HP with this question but it hasn't responded. What can I do?

JANICE DRIGANS, FRIDLEY

A The ink gradually evaporates from the color cartridges whether you print with them or not.

While that's irritating, the larger problem with the Photosmart is that a dry color ink cartridge prevents you from printing at all. If you want to print in black and white, the only solution is to buy a new color ink cartridge.

The HP Support Forum (tinyurl.com/2ewe5wu), where there are several complaints about this, says the printer could be damaged by running with an empty cartridge.

But if that's true, why was it designed that way? Apparently to make money. Printer manufacturers make little profit on the sale of low-priced printers, and make it up by selling expensive replacement ink cartridges. See a 2009 New York Times article entitled "H.P. Tries to Keep the Ink Flowing," at tinyurl.com/332pgrl.

E-mail tech questions to steve.j.alexander @gmail.com, or write to Tech Q&A, 425 Portland Av. S., Minneapolis, MN 55488-0002. Include name, city and telephone number.