Hi. I'm new to Pi-Hole. I've had it running maybe 2-3 weeks and then I log-in today and find the "update available" message via the admin web interface. I of course click the update link only for it to link externally out to github (an odd behavior, it should come here to this site). I do a Google search and find myself here on this site looking at the:
How Do I Update To This Version?
Running the pihole -up command will update your Pi-hole installation.
SO okay I fire up Putty and enter the command, it takes a good while to finish and when I come back I try to do what I originally sought out to do, edit my whilelist; nada. My whitelist is now blank and I get an error when I try to edit it further. I used the web interface to restart but it didn't help.
It's very likely that your web browser is still trying to use code from the previous Pi-hole version.
Try a force-refresh in your browser on the whitelist page (press Ctrl + F5).