OutOfMemory after update KB4534273

[W_Grooters]

WindowsServer 2019, Hyper-V instances: 1 application server, 4 rdhs servers. Database and related server run on application server, applications run by users run in remote sessions. 

Last application update has been done on DEc. 24th last year. No issues, all worked fine.

Last Wednesday evening, this update (and some others, I don't have th whole list) is installed on all servers (physical and virtual). No problems on Thursday but since Friday, processes crash after some time: on either OutOfMemory or access violtation due to failure of creating objects (result is null on reference) on any location in the program after requesting memory

No changes in application and database server (certain) or configuration (assumed).

I assume this update since it also contained an update for Windows Virtualization.

Could anyone give a hint what could cause these sudden occurring OutOfMemory messages, based on the Windows update?

[#2]

Might try removing the update as a test. I'd also engage the application developer for help debugging the process.

[#3]

Did not work, reversed to state before update by restroring backup. That improved matters, even better after moving back to WindowsWerver2016. No more memory issues but still quite slow - which seems to be a matter of configuration (WAY to little memory configured for each VM given the number of users on it). The issue with WindowsServer2019 seems to be related to this (bad) configuration as well.

Consider problem 'solved' - we now know the cause of problems: badly configured system, which became worse after this update