From what I read, there will not be Windows 8 drivers for the Dell 968 Printer.
You can try this, it may of may not work...
First run Delete Print Jobs to remove any stuck print job in the queue.
Disconnect the printer.
Hit the Windows key and the x keys at the same time, programs and features, Dell 968 printer, uninstall.
Restart your computer. Make sure the printer is removed. Manual Printer Driver Removal
Download the Vista 32-bit drivers for Windows8 32-bit or the Vista 64-bit drivers for Windows8 64-bit. Install the Vista drivers in the Vista Compatibility mode You'll get a message, the printer is not connected. Connect the printer at this time(powered on).
Links to the drivers can be found at...
Dell 968 & 968w All-In-One Printer owners thread (W7)
Remember virus programs and firewalls will block communications. If you didn't install any virus program, then Windows Defender is the virus program. Try reading, Allow Printer past Microsoft Essentials/Windows Defender