Hello, I have HP LaserJet Pro P1606dn. By

SOURCE: my hp laserjet 4 plus printer cannot print excel files

wherer are you printing this, A4 is european, north america would use letter, etc..
if you go to control panel, open the printers and faxes folder, right click the printer in question, a window will pop up, click on properties.. a new window should open. click on "Printing Defaults" or "Printing Preferences" then click on "Advanced" ( I believe it should be to the lower left) that will open another window, in paper size make it Letter if your in N America, A4 for Euro.. this will set the deafult print..
Click ok, then print a test page from the general tab..

The reason you getting this LOAD LETTER message. your excel page setup is set to print to letter, your machine is set to print top A4

If you open Excel then go to Print then a window should pop up where you select the printer you want to use, click on Properties, then Lay out, then Advanced, and input the correct paper size before you print.

does this happen with all excels files, or one particular?
Create a new Excel file, and try printing it.. possibly could be in that particular file. I have seen this happen alott particulary with PDF files.. Where the incorrect paper size is in the file..

SOURCE: HP Laserjet 3050, need to press ok each time printing

did it work before? check paper size for trays - suspect it is set for a4, change to letter size

SOURCE: HP Laserjet 5000dn

if you using office go to page setup and select the tray(s) that you want to use for the first page and other pages ( both must be the same ) unless you only want the first page as letter head and the rest on plain paper or something along those lines ?

Also if you go into the properties of the printer and go to advanced and then click on the printing defaults button and see if the options in there are the same or different to whats in printing preferences.

If they are set to tray 1 then it will default to tray 1

SOURCE: Paper default keeps changing

you have to uninstall the program and reinstall all the drivers again.

SOURCE: hp laserjet p3005dn tray1 manual feed problem

you can choose mp first in "paper handing" printer menu or print tray1 is A4 default in properties of printer software.