The usual method of sharing a printer is to have it connected to one computer (the "Host" computer) and, in its Properties, set it as "Shared". It can then be installed as a "Network Printer" (as opposed to a Local Printer) in the "Client" computer so that it can print over the network.
However, the HP PSC 1215 is a multi-function Printer, Scanner & Copier and Windows "File & Printer Sharing" doesn't support the sharing of scanners, only printers. You can still share it as a Printer, but Scanning and Copying will only be possible from the PC it is actually connected to.
Network Printer Setup
1) Connect the printer to the “client” PC, as though it were to be used with that computer, and install it. This ensures that it has all the necessary software/drivers on board.
2) Reconnect it to the "host" PC and, in its Properties, set it as "shared". In the client’s "My Network Places" (or Network Neighborhood), the printer should then appear as a shared resource of the "host" PC along with any shared folders. Double clicking the printer in the remote PC should automatically install it as a "network printer" in the “client”. This means that the “client” now has the same printer installed twice – once as a “local” printer and again as a “network” printer (with a bar under the icon to indicate a network device). If you are always going to print via the network, you may want to set the "network printer" as the default.
Otherwise, have a look at this Microsoft article. It is an old article written for Windows 95, but the basic principle for installing the network printer should still be valid.
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