You should assign the printer a static IP address so then it won’t be offline on your network, google your printer model to see how to access the web interface to assign a static ip address.
Also you should upgrade to windows 10 from 8, windows 8 is not supported by microsoft anymore.
For a specific system all the shared printer goes offline when system restarts, it can be connected but each time all the connected printers goes offline.
PC is connected in static,
OS Windows 8
any update helps.