I installed the April 2018 update on a workstation yesterday. Today I first upgraded PRTG to 188.8.131.523, but still all was working well.
Then I updated the "server" running PRTG with the April 2018 update. After that, the workstation I updated can't send data. I get the dreaded "A connection could not be establised - PE015" error.
Just to check if it was a fluke, I updated another workstation. Same thing. It worked, then it did not.
I usually have to do these tricks: https://kb.paessler.com/en/topic/203-how-can-i-monitor-wmi-sensors-if-the-target-machine-is-not-part-of-a-domain … to get PRTG working again after huge windows updates, but I checked every setting and it should be OK.
And on the PRTG "server" I've used the WMItest.exe tool. Which can read data from both machines.
What am I missing? Is it something with the April 2018 update?