Just by now I resolved Error 137

I had to disable Comodo Secure DNS in order to get it to work. Anyone got any alternative DNS?

Open DNS, Google DNS, Norton DNS,…

I have exactly the same issue : Error 137.
I noticed it with the 17.3 update.
I do not seem to recall the same problem in 17.0
I’m a developer this is a serious problem.
Why would this Secure DNS ‘service’ do a look-up for a local request like http://localhost:1488 ?
By the way, running Fiddler in the middle makes the problem go away.
Still, this is a serious issue.
Will this be addressed ?