Hi @ranger55 Firstly can you check you have the latest firmware on the Samsung Support sitehttps://www.samsung.com/uk/support/ An idea to reset the Network as it may be due to unstable network/wifi. settings-General-Network-Reset Network. If still issues try a soft Reset of the Tv by holding in the power button on the Smart Remote for around 5 seconds until the Samsung logo appears. If to no avail try a Factory Reset via the settings or by unplugging Tv for a few minutes. other ideas are to reset the router (unplug from mains) and to change the DNS from Automatic to Manual. Go to Network-Network Settings-DNS Settings. Change from Automatic to to 8.8.8.8 or 8.8.4.4 (the Google servers) If wish to try an alternative one is Open DNS 208.67.222.222 or 208.67.220.220 some detail in this article https://www.lifewire.com/free-and-public-dns-servers
I do not work for Samsung or make Samsung Products but provide independent advice and valuable contributions.
