service tag worked for recovery image but not for drivers

It appears that my service tag issue was browser-related. I worked my way through four browsers before the Dell website accepted my service tag and I was able download both the Dell Windows 7 recovery image and the drivers specific to the Optiplex 790.

Contrary to the replies I received, it *is* possible to get a Windows 7 recovery image from Dell, based on the service tag, at least for business class machines. I have done so for the Optiplex 790, Optiplex 7010, and Latitude E6420.  These are the original Windows 7 images; after installing them, you will need to go through a few hours of running updates to bring the system up to date. The recovery image will be the same version of Windows 7 installed originally installed (for business machines, Pro 32 or 64 bits) Information on how to do get the recovery image can be found here:

http://www.dell.com/support/article/us/en/04/sln299044/how-to-download-and-use-the-dell-os-recovery-image-in-microsoft-windows?lang=en

I have used these images to rebuild the machines listed above after hard drive upgrades.  The service tag also lets one get a list of exactly the drivers needed for a particular machine, including any bios upgrades. You can do this by entering the service tag number here:

http://www.dell.com/support/home/us/en/04?app=drivers&c=us&l=en&~ck=mn

Do the Windows 7 install first, then BIOS, then chipset drivers, then other drivers. Have them all on a USB stick drive and you won't need wifi or ethernet access until you've finished updating everything. If you wish to block Windows 10 upgrades, the easiest way to do so is with a tool called GMX Control Panel, which can be found here:

cheers - bill