Thank you both for this useful additional information.
I reloaded my printer driver, watched the video, thought I folllowed all instructions.
I loaded an A4 sheet of GFS, through front loader, it loaded as per video
Chose Gold Fiber Silk, chose the GFS profile downloaded from Ilford, Chose media type PPPSG , went to the Printer button, then in the Printer Window checked my media type, correct , then pressed Print.
Error message.
See these three screen photos
Am I dumb?
What am i doing wrong?
No you are not dumb. This stuff can be confusing.
But you are doing something wrong.
Firstly - Eric - you can load GFS or any other such papers either through the FFA path or the top feed path. It doesn't matter as long as both the printer and the driver are in agreement about the chosen paper path. FFA is required for heavy paper to avoid damaging the printer. Anything from GFS lighter is usable in the top feed, which has the advantage of being easier to load.
Secondly, back to Kees - the point above is the key - assuring agreement between the printer and the driver on the paper path.
Thirdly - Mike - something about your version of the P800 driver and mine that don't cohere. I believe mine is the latest version for OSX. Epson has cleaned-up the paper path business between Page Set-up and the Printer settings in the driver.
Fourthly, back to you Kees - please have a look at my appended screen grabs using the current version of the Epson driver for the P800 on OSX. In Page set-up you select the paper size and whether it is sheet or roll, border or borderless. This example, sheet with borders. This menu has been reduced from previous driver versions, because the paper path is now specified in the Printer tab (except for Posterboard which is selected in Page Setup). In the printer tab you specify the Paper Source where here I have chosen Front Fine Art (and that means the paper really must be loaded from the FFA feed otherwise the mismatch error message will appear).
Fifthly, Kees, please note my settings underneath. I use Superphoto 2880 to assure highest quality from the printer (slower but better, they say). I keep High Speed OFF for the same reason, and keep Finest Detail OFF, because that is not useful for most normal photographs - it is more applicable to graphics and very high density images.