Running examples in 'future-Ex.R' failed
The error most likely occurred in:

> ### Name: nbrOfWorkers
> ### Title: Get the number of workers available
> ### Aliases: nbrOfWorkers
> 
> ### ** Examples
> 
> plan(multiprocess)
Warning in socketConnection("localhost", port = port, server = TRUE, blocking = TRUE,  :
  port 11835 cannot be opened
Warning in doTryCatch(return(expr), name, parentenv, handler) :
  NAs introduced by coercion
Warning in doTryCatch(return(expr), name, parentenv, handler) :
  NAs introduced by coercion
Warning in doTryCatch(return(expr), name, parentenv, handler) :
  NAs introduced by coercion
Warning in doTryCatch(return(expr), name, parentenv, handler) :
  NAs introduced by coercion
Warning in doTryCatch(return(expr), name, parentenv, handler) :
  NAs introduced by coercion
Warning in doTryCatch(return(expr), name, parentenv, handler) :
  NAs introduced by coercion
Error in socketConnection("localhost", port = port, server = TRUE, blocking = TRUE,  : 
  Failed to launch and connect to R worker on local machine 'localhost' from local machine 'CRANWIN'.
 * The error produced by socketConnection() was: 'cannot open the connection'
 * In addition, socketConnection() produced 1 warning(s):
   - Warning #1: 'port 11835 cannot be opened' (which suggests that this port is either already occupied by another process or blocked by the firewall on your local machine)
 * The localhost socket connection that failed to connect to the R worker used port 11835 using a communication timeout of 120 seconds and a connection timeout of 120 seconds.
 * Worker launch call: "D:/RCompile/recent/R-36~1.0/bin/x64/Rscript" --default-packages=datasets,utils,grDevices,graphics,stats,methods -e "#label=future-Ex.R:190676:CRANWIN:CRAN" -e "try(cat(Sys.getpid(),file=\"D:/temp/RtmpcZE8YS/future.parent=190676.2e8d41d9a5bd8.pid\"), silent = TRUE)" -e "parallel:::.slaveRSOCK()" MASTER=localhost PORT=11835 OUT=/dev/null TIMEOUT=120 XDR=TRUE.
 * Worker (PID 185804) was successfully killed: TRUE
 * Troubleshooting suggestions:
   - Suggestion #1: Set 'verbose=TRUE' to see more details.
   - Suggestion #2: On Windows, output from worker when using 'outfile=NULL' is only visible when running R from a terminal (not a GUI).
Calls: plan ... tryCatchList -> tryCatchOne -> <Anonymous> -> <Anonymous>
Execution halted