Just wanted to post a solution to this as I struggled to find one online and hopefully this will show up in future searches for people with a similar problem.
I finally got my Epson 7600 printing after connecting it via Ethernet and installing Epson NetConfig to assign its manual IP address.
I downloaded the Epson 7600 driver from their website but as they don't have a Windows 8 driver I had to download a VISTA driver instead. (In Windows 7 you could click on the properties of the setup.exe file and run in Vista compatibility mode and it'd work. Windows 8 doesn't do this).
Once you've got your driver file downloaded you need to override windows 8's rules to not install unsigned drivers as clicking on the setup.exe file will do nothing or bring up an error message.
To do this follow these instructions:
click here you've done that you go to Devices and Printers and add the printer manually. When asked what printer and driver you want to install you'll have to do this manually as it wont appear on the 'signed driver' list. Click 'have disk'. navigate to where you've downloaded the driver and click on the .inf file.
The driver will now be able to be installed without error messages or windows cycling through the install procedure.
I don't know if this will work if connected by USB as my printer is shared across a network and has an ethernet card installed (£25 on eBay).
Forgot to state that I needed to configure my port to use the RAW protocol and not LPR. For some reason when using LPR the printer would through out a printer error about 4/5 of a way through an A1 document.
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