I have a VB.NET application that connects to a remote server, which I have no authority whatsoever, via a username/password, retrieves some data and populates a local database.
Lately the application stopped working and began sending the error
System.Net.WebException: The request was aborted: Could not create SSL/TLS secure channel.
or
Inner Exception: System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a send.
Going through this post and performing what is recommended there, I am still facing the same issue from a particular computer running Windows Server 2019 that was upgraded from 2012, porting the executables to another computer it runs fine.I ran IIS Crypto on both server and other PCs and applying their recommended best practices on both, it persisted.
I concluded that this particular PC has some outdated cipher or certificate that is preventing the connection.
How can I get a list (cmd, PowerShell, …) of whatever is causing the security issue from the 2 computers in orderto compare and find the culprit?