Have you by any chance changed/upgraded the OS on the computer? The last patch from DELL for Printer 948 seems to be for Win Vista, but you can run it in compatibility mode for Windows 7 and Windows 8 (windows 8 compatibility mode works for windows 10 as well).
This patch will just remove the existing dell printer on your computer, so you can start from scratch.
Then try and download the appropriate driver for you. This one is for my computer as it's 64 bit:
Once downloaded, make sure you right click > properties > compatibility >> change the compatibility according to your Windows OS apply and then run the driver installation and it should hopefully work ok :-).
I have a 948 Dell ALL-IN-ONE Printer, I have a Dell Desktop Inspiron 530 running SP2. I purchased all this at one time from DELL about 1 1/2 yrs ago. When I received it all I did was install the printer drivers and started printing and everything was fine until about a month ago my 16 yr old son can to me and said the computer will not boot up sure nuf there was a screen being displayed with 1-8? options to choose from anyone of these options you chose would not do anything even though it allowed you to select them. SO to sum up the story I re-installed the OS from scratch including patches etc, with the restoration cd's DELL provided and printer drivers as well that DELL provided. And this is where I am, UNABLE TO PRINT. Anyone's help would be a GOD send since I have researched this thing until I'm blue in the face. signed STRESSED