Hi, we are getting the following error when trying to connect to a DB instance on Oracle 12 g on Vmware.

This was working fine up until the latest Windows updates which came down last friday.
We have been able to replicate this by rolling back to a previous snapshot with no updates, the updates re-applied overnight and the again encountered the DB connection issues.
Has anyone experienced something similar? If so what updates did you exclude and what did you do to fix this?