I finally came around to upgrading to 1.4.0 from 2015R2 after not seeing too much complaining around these parts re the new release. The one problem I am seeing immediately is the URL in my alert emails is now all wonky.
The "MyNLSCluster#" thing is a placeholder, clearly, in the interest of privacy. One thing I did note is that the equals "=" sign pops up as the 46th character in the URL in both instances.
Looks like it defaults to Default Template anyway. I didn't make any changes on purpose, if that's what you mean. The only thing after the update I had to do was set the Interface URL on the Global Settings screen. Without it (right after the update) the sent links would start with 172.0.0.01 which clearly wasn't helping anyone. The cluster hostname and interface url are set to the same thing.
My coworker has actually chased this down to being an issue with exchange. He did a TCPDump to make sure the URL was leaving LogServer correctly, and it was. Can you check the exchange logs and see if there is anything in there?
I got my exchange guy looking into it. While we wait, my concern is that the email format has changed between 2015R2 and 1.4 releases of NLS and that is really the underlying problem here. As you said - your coworker confirmed this happening with Exchange, so it's not just my exchange configuration, it's everyone out there who is using NLS with exchange.
So what it looks like to me is that the email code output by NLS (and interpreted correctly by Postfix) gets messed up with exchange. It's like one of those websites where the HTML is technically correct, but it only looks right in IE.
Any information you find out from the exchange logs could be helpful. We changed some things with emails last release to enable the use of templates, specifics I would have to reach out to the developers. We don't use exchange here, so any information you can gather will be helpful.