Greetings and salutations
Issue: undertook a clean install of exchange server 2019 on a windows server 2019 core install (it's a hyper-v infrastructure and the all servers are VMs). Everything was fine as i could log in using the admin account in my AD so i left it alone after installation as i was in no rush to get it up and running e.g. OWA, etc
however, since Microsoft security announcements I undertook windows security updates over the pass week (playing catch up, installed the server and exch in june), however now when i go to https://FQDN/ecp i cannot login using the admin AD accounts default (administrator) and domain specifically created some years ago and all other servers can use the AD Admin login details fine.
Question: what can i do to check exch support on AD Admin accounts? Do I need to reinstall? anyone else had issues with exchange since updates?
My Options: Fail safe and drastic
(1) restore an old check point which I created in June, so will not have the latest updates which is fine and if that works then i know windows updates have crashed my exchange, bad Microsoft but not unexpected.
(2) check AD Admin accounts to make sure their exchange compliant (my first choice) and/or create new user and add to the ECP admin
(3) complete reinstall of OS, fully update, then install exchange again and see what happens (fail safe last man stand resort)
(4) alternative options please inform?
Many thanks and godspeed in advance