Have you recently enabled a VPN? If so, this might be the problem. Try turning the VPN off and see if that helps.
Is there a corporate or otherwise external firewall getting in the way? Contact the IT people maintaining the firewall and ask for permission. Does your Antivirus software allow Quicken to connect to the Internet? Quicken needs to be able to establish outbound Internet connections for the program to work.
https://www.quicken.com/support/advanced-data-file-troubleshooting-correct-problems-quicken-windows
Once you get the chance let us know what you're able to find out. From there we'll see what we're able to do next.
Thanks,
Quicken Francisco
Scott Baines said: although my user names are not the same on my desktop and laptop, they are one word user names so i don't have the same issue as Susan
Scott Baines said: I just switched my PC from Ethernet to Wireless to see if there was a difference. The "check update" works fine over the wireless network. I don't get the "unknown error". The wireless and ethernet network both are on the same gateway/router (Xfinity). I guess it could be my ethernet network adapter but I don't have any other issues other than Quicken Check updates. No idea how to figure this one out.