sendmailR works for me on Windows 7. I referenced http://cran.es.r-project.org/web/packages/sendmailR/sendmailR.pdf
smtpServer= info for Outlook 2010 is in File -> Account Settings -> Account Settings -> double click your account -> text in “Server” box
library(sendmailR)
#set working directory
setwd("C:/workingdirectorypath")
#####send plain email
from <- "you@account.com"
to <- "recipient@account.com"
subject <- "Email Subject"
body <- "Email body."
mailControl=list(smtpServer="serverinfo")
sendmail(from=from,to=to,subject=subject,msg=body,control=mailControl)
#####send same email with attachment
#needs full path if not in working directory
attachmentPath <- "subfolder/log.txt"
#same as attachmentPath if using working directory
attachmentName <- "log.txt"
#key part for attachments, put the body and the mime_part in a list for msg
attachmentObject <- mime_part(x=attachmentPath,name=attachmentName)
bodyWithAttachment <- list(body,attachmentObject)
sendmail(from=from,to=to,subject=subject,msg=bodyWithAttachment,control=mailControl)
In addition, multiple files can be sent by adding another mime_part to the msg list as follows (I also condensed it):
attachmentObject <- mime_part(x="subfolder/log.txt",name="log.txt")
attachmentObject2 <- mime_part(x="subfolder/log2.txt",name="log2.txt")
bodyWithAttachment <- list(body,attachmentObject,attachmentObject2)