r - sendmailR を使用して R からメールを送信できませんでした

Question

R で mailR ライブラリを使用してメールを送信しようとしています。これは私のコードです：

install.packages("sendmailR")
library(sendmailR)
sender <- "myemailid@umd.edu"
recipients <- "myemailid@gmail.com"
send.mail(from = sender,
      to = recipients,
      subject = "Subject of the email",
      body = "Body of the email",
      smtp = list(host.name = "exch.mail.umd.edu", port = 465,
                  user.name = "myemailid@umd.edu",            
                  passwd = "mypassword", ssl = TRUE),
      authenticate = TRUE,
      send = TRUE)

このコードは私に次のエラーを与えています:

org.apache.commons.mail.EmailException: Sending the email to the following server failed : exch.mail.umd.edu:465
at org.apache.commons.mail.Email.sendMimeMessage(Email.java:1410)
at org.apache.commons.mail.Email.send(Email.java:1437)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at RJavaTools.invokeMethod(RJavaTools.java:386)
Caused by: javax.mail.MessagingException: Could not connect to SMTP host: exch.mail.umd.edu, port: 465;
nested exception is:
java.net.SocketException: Connection reset
at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2055)
at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:697)
at javax.mail.Service.connect(Service.java:386)
at javax.mail.Service.connect(Service.java:245)
at javax.mail.Service.connect(Service.java:194)
at javax.mail.Transport.send0(Transport.java:253)
at javax.mail.Transport.send(Transport.java:124)
at org.apache.commons.mail.Email.sendMimeMessage(Email.java:1400)
... 6 more
Caused by: java.net.SocketException: Connection reset
at java.net.SocketInputStream.read(Unknown Source)
at java.net.SocketInputStream.read(Unknown Source)
at sun.security.ssl.InputRecord.readFully(Unknown Source)
at sun.security.ssl.InputRecord.read(Unknown Source)
at sun.security.ssl.SSLSocketImpl.readRecord(Unknown Source)
at sun.security.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source)
at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)
at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)
at com.sun.mail.util.SocketFetcher.configureSSLSocket(SocketFetcher.java:543)
at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:348)
at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:215)
at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2019)

ホスト名、送信者、および受信者アドレスがすべて正しいにもかかわらず、このエラーの背後にある理由を取得できません。Windows 10 と R 3.2.2 を使用しています。