it has all my business files on it.

My primary computer is Windows XP - the networked computer is Windows 95. I said - don't laugh.

This has worked for me for years. I don't know what changed to not allow me to print from the Windows 95 computer.

I use both of these computers strictly for my business files.

I have a separate laptop that I use for the Internet and my e-mails.

The main reason I still use the Windows 95 computer is that I have an expense report program who's company has gone out of business - but this original expense report program happens to be the one that I've used throughout the history of my business.

the Windows 95 computer because that is the computer that has the program on it.

Again I always was able to print from this computer to my networked printer - but I must have inadvertently done something that turned that function off. When I hit print the dialog box comes up but in the Owner column it says Administrator. Somehow I think I need to go into my XP computer that is the primary computer in this network and change some setting as the administrator of this network. But I don't know where to go to do this and what to do when I get there.

or on the Windows XP computer or somewhere on the network.

Are you sure the Windows 95 computer is still on the network? No problem with the cables and or
switch/router? Can you ping the Windows XP computer from the Windows 95 computer?

I can go from one computer to the other and back by pressing a button on a switching device.

Is go to the Printers & Faxes in both computer menus and make sure that the printer shows up in both. My first reaction is that you may have a printer driver problem.

Report back with the findings of your investigation.....

The drivers are still there.

Try sharing the printer again. I'm assuming it's plugged into the XP machine, so do this:

Go to Printers and Faxes again
Right click on the HP printer, select Properties
Go to the second tab at top; Sharing
Ensure that 'Share this Printer' is selected.

See if that changes anything.

Actually doesn't matter if they worked before the first thing I would try is restarting the router. I have seen printers go down because of the router many times.

I would start there before getting crazy. Especially since they worked before.