NSURLErrorDomain error -1100

Hi,

I have a 2018 iMac 27" that has been updated to 10.14.6 Mojave. I also have an iPhone XR running iOS 13.1.2. I noticed that when I plug in the iPhone, the Photos app could not connect to the iPhone to import pictures. It gives the message. "An update is required" and when I click 'Install', I get the error message "Installation Failed. Can't download the software because of a network problem." I thought it was my VPN, so I turned off NORDVPN, but the error persisted. I thought it was MalwareBytes, so I uninstalled it, but the error persisted. I thought it could be AdGuard, so I disabled it, but the error persisted.

Then I tried to run the apple App Store to see if there were updates to software that maybe was causing some issue. But the App Store said there were no updates. Really? Nothing? In the back of my mind it seemed strange.

I tried loading Software Update from System Preferences, but it gives the error "Unable to Check for Updates. Make sure you are connected to the internet." Of course I'm connected to the internet!!

I went into terminal and tried :

$ softwareupdate -l

Got back :

Software Update Tool

Finding available software

The operation couldn’t be completed. (NSURLErrorDomain error -1100.)

Now I was getting frustrated! I did a little google sleuthing, and came upon a post that suggested a conflict with duplicate Verisign certs. So I removed the duplicate certs under System with KeyChain Access. Rebooted. Problem remains. Removed certs under Login as someone else posted. Problem remains.

Then I came upon a post that someone said it resolved on its own in a day. So I waited a couple days and tried again. Problem remains.

My computer is not connecting with Apple Update servers for some reason. Can anyone shed some light on where to look for a log file to figure out what is wrong?