If you have the Ricoh SP213w and it keeps forgetting the WIFI when its been turned off, I can help.
Firstly, go to settings, then try to add the printer as normal. The best way you can do this by click windows button, settings, devices, add printer. It will then search for your printer, but not find your printer. Do not be upset. You then click the text, “the printer I want wasnt listed”. A dialogue box with open, and the first box says “my printer is a little older, help me find it”. Make sure that is enabled and click next. It should then find your printer, install it as normal.
Now here is the problem. When the printer is installed, windows links an IP address to the printer. However when you turn the printer off, it may lose that IP address. So when it is turned back on it maybe allocated a different IP address so windows can not find it.
The solution
Now that you have installed the printer, go back to the settings page, then devices. It should now be listed in the printer section. Then click on it, and click manage, then printer properties. A diologue box will open, click on ports. There will be a tickbox on the IP address that the printer is currently at, make a note of this. Then open a web browser like chrome and go to that ip address the printer was noted at.
You are now in your printers admin page. You then just need to go to the network settings and give it a static ip. We need to pick a number that isnt going to be used, I suggest 192.168.1.213 .
Ensure your gateway and dns are correctly setup.
Then click save. Your printer will now never change IP.
Now, you need to reinstall it following the first steps, as the old installation will not work. Once you have done this, you can delete the first installation, and you should have the printer installed and it wont be lost when it is turned on and off.
Good luck!