Yours seems to be slightly different. Mine is Access Denied and yours is Low Memory.
Yes, Windows Defender Firewall is fine, rules in place for both Beats and Graylog API.
Can anyone else spin up a VM of a fresh install of Graylog with a Windows 10 client and see if they get the same issue in the debug logs? These are both clean installs using the default config files.
The fresh Graylog and Windows client were spun up outside of our test and production environment therefore removing that as a variable. I used a box fresh VMware server.
I just built out a fresh Win10 machine in workgroup (no domain) with nothing but Graylog Sidecar installed, patched it all the way to current. Current default winlogbeat configuration applied and all standard win log files are flowing to Graylog. Is there anything you want me to test?