Insufficient memory on only one of two HP Laserjets 2605dn

Any 10 errors are related to cartridges and the memory chips on them. If you just changed a cartridge then it is possible that it is defective. Try putting the old cartridge back in. Also ensure that the cartridges are all seated fully and that the front door closes properly as this can trigger the error as well.

Does it always happen? does it always happen from a particular program? may need to upgrade your memory capacity.

HP has now admitted their firmware update causes an irreversible corruption in the formatter board. It is hard to get them to do this, but I understand they will repair at no cost if they can determine that you did install this update.

Is this on a Laserjet 2600?
On some other laserjets it indicates a problem with the memory.

Try this:

20 MEM OVERFLOW
20 INSUFFICIENT
MEMORY
Indicates a memory overflow. Too much data is being sent
to the printer and the printer has run out of memory.
Pressing the [Continue]* key causes the printer to print only
the information it received. If the error persists, it may be
necessary to simplify the print job (such as fewer fonts and
less graphics information), or have the customer purchase
additional memory.

Please refer here to myearlier solution to the same problem, which was very helpful.
Let me know if any further clarification/ assistance is required.

Good Luck!
Appreciate generously, if the solution could have been of any help!
CreativeTECH

Most likely the cartridges are out of toner. Or something is obscuring the path of the laser writer. If changing the cartridges does not solve the problem the machine will need servicing. Service manuals are available but not as comprehensive as necessary to fix this problem. Below is a very good DIY guide, but be very careful if you choose to do this yourself and follow his directions precisely.

http://www.reeves-hall.net/tech-gadgets/fixing-washed-out-colour-on-hp-color-laserjet-2605/

Laserjets have limited amount of ram to keep large docs in memory, you can increase the document or in windows have it spool on your machine first.

all the drivers are available from this link, including vista and vista64.

http://h20000.www2.hp.com/bizsupport/TechSupport/DriverDownload.jsp?prodNameId=1140731&lang=en&cc=uk&prodTypeId=18972&prodSeriesId=1140727&taskId=135

I found this page in the User Guide. Maybe it will be helpful.
"If the printer has a new memory DIMM installed, all Windows users of the printer must set the printer driver to recognize the newly added memory. Macintosh computers automatically recognize new memory.

To enable memory for Windows
1. On the Start menu, point to Settings, and click Printers or Printers and Faxes.
2. Select this printer and select Properties.
3. On the Configure tab, click More.
4. In the Total Memory field, type the total amount of memory that is now installed.
5. Click OK."

Give this a try and if it doesn't work, let me know and I'll keep looking.