Azure Log Analytics - The client and server cannot communicate, because they do not possess a common algorithm

The client and server cannot communicate, because they do not possess a common algorithm

Well the error itself reveals a little bit of info about what it involves, algorithms.
Where are algorithms used? Well secure connections, such as TLS.

If you have TLS 1.2 enabled chances are your application defaults to TLS 1.0 which you probably have disabled just a did for TLS1.1.

If you have servers that have .Net 4.5.2 and below, and you have a .Net application that is trying to connect to something using TLS or Schannel, it will default to TLS 1.0 and fail if you have disabled tls 1.0 and 1.1.
But you can fix this by adding a registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v4.0.30319

and

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\.NETFramework\v4.0.30319

called SchUseStrongCrypto and set that to 1.

After a reboot, the .Net applications will be forced to use TLS.1.2 and connect.

Full error from the monitoringAgent.log file:

Failed to connect, exception : System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a receive. ---> System.ComponentModel.Win32Exception: The client and server cannot communicate, because they do not possess a common algorithm