I have remote SQL Server 2019.
On my machine I’m using SSMS 19.3 in order to connect to the SQL Server (and no problems with the connection to the SQL Server).

Why SSMS 20.1 (that I installed on my machine in addition to SSMS 19.3) can not connect to the SQL Server?

SSMS 20.1 shows this error:

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Cannot connect to {server IP},{server port}.

A connection was successfully established with the server, but then an error occurred during the login process. (provider: SSL Provider, error: 0 – An existing connection was forcibly closed by the remote host.) (Framework Microsoft SqlClient Data Provider)

For help, click: https://docs.microsoft.com/sql/relational-databases/errors-events/mssqlserver-10054-database-engine-error

Server Name: {server IP},{server port}
Error Number: 10054
Severity: 20
State: 0

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Program Location:
at Microsoft.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action1 wrapCloseInAction) at Microsoft.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose) at Microsoft.Data.SqlClient.TdsParserStateObject.SNIWritePacket(SNIHandle handle, SNIPacket packet, UInt32& sniError, Boolean canAccumulate, Boolean callerHasConnectionLock, Boolean asyncClose) at Microsoft.Data.SqlClient.TdsParserStateObject.WriteSni(Boolean canAccumulate) at Microsoft.Data.SqlClient.TdsParserStateObject.WritePacket(Byte flushMode, Boolean canAccumulate) at Microsoft.Data.SqlClient.TdsParser.TdsLogin(SqlLogin rec, FeatureExtension requestedFeatures, SessionData recoverySessionData, FederatedAuthenticationFeatureExtensionData fedAuthFeatureExtensionData, SqlClientOriginalNetworkAddressInfo originalNetworkAddressInfo, SqlConnectionEncryptOption encrypt) at Microsoft.Data.SqlClient.SqlInternalConnectionTds.Login(ServerInfo server, TimeoutTimer timeout, String newPassword, SecureString newSecurePassword, SqlConnectionEncryptOption encrypt) at Microsoft.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, SecureString newSecurePassword, Boolean ignoreSniOpenTimeout, TimeoutTimer timeout, Boolean withFailover, Boolean isFirstTransparentAttempt, Boolean disableTnir) at Microsoft.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(ServerInfo serverInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString connectionOptions, SqlCredential credential, TimeoutTimer timeout) at Microsoft.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(TimeoutTimer timeout, SqlConnectionString connectionOptions, SqlCredential credential, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance) at Microsoft.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, SqlCredential credential, Object providerInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString userConnectionOptions, SessionData reconnectSessionData, ServerCertificateValidationCallback serverCallback, ClientCertificateRetrievalCallback clientCallback, DbConnectionPool pool, String accessToken, SqlClientOriginalNetworkAddressInfo originalNetworkAddressInfo, Boolean applyTransientFaultHandling) at Microsoft.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection, DbConnectionOptions userOptions) at Microsoft.Data.ProviderBase.DbConnectionFactory.CreateNonPooledConnection(DbConnection owningConnection, DbConnectionPoolGroup poolGroup, DbConnectionOptions userOptions) at Microsoft.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
at Microsoft.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource1 retry, DbConnectionOptions userOptions) at Microsoft.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource1 retry, DbConnectionOptions userOptions)
at Microsoft.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource1 retry) at Microsoft.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource1 retry, SqlConnectionOverrides overrides)
at Microsoft.Data.SqlClient.SqlConnection.Open(SqlConnectionOverrides overrides)
at Microsoft.Data.SqlClient.SqlConnection.Open()
at Microsoft.SqlServer.Management.UI.ConnectionDlg.Connector.<>c.b__26_0(UIConnectionInfo uici, IServerType ist)
at Microsoft.SqlServer.Management.UI.ConnectionDlg.Connector.ConnectionThreadUser()

An existing connection was forcibly closed by the remote host

The remote SQL Server 2019 is not configured with Force Encryption enabled (in SQL Server Configuration Manager I see ForceEncryption = “No”).
In SSMS 20.1 I tried different connection options (Encryption: Optional, Mandatory; checked and unchecked “Trust server certificate” checkbox) – in all cases I see the same crash (above).
In SSMS 19.3 I have unchecked “Encrypt connection” and unchecked “Trust server certificate” – and I have no problems with the connection to the SQL Server.