Help on getSymbols

Josh,   I have been using the get symbols to bull data from Yahoo via the following code and generally works well.

FromDate = "2002-05-24"
ToDate = "2016-03-17"


userInput=c("SHW","ABC","LEN","PCLN","HAR","ETN","RRC","PNR","MO","MAT","SNDK","EW","SPLS","AGN","F","MMM",
                   "SWK","EA","KSU","MLM","FCX","XRAY","BDX","DOW","LUK","PHM","TMO","DHI","COH","HOT","STZ","LOW","ADS?,
                   "SWN","REGN","CSC","VFC","CI","HPQ","CA","TE","PWR","RF","BAX")
for (i in userInput)
{
  getSymbols(Symbols=userInput, src="yahoo", from = FromDate, to = ToDate, auto.assign=TRUE, return.class="data.frame")
}

My issue is that many times it takes a really long time to complete,  like upwards to 20-30 minutes.  Sometimes the process terminate with an error message.   I am trying to replicate it, but no luck right now it is just running.  The error indicated something about a header being off.

I have a hunch that something is not recognizing the download has completed and can?t terminate the call.

I do notice that when I manually stop the get symbols  call after a short time ( 1-2 minutes) all of my data I asked for will be in the global environment.

This is preventing some automation I would like to do for my models.

Do you have any suggestion on what could be causing this or any solutions?

Thanks  Dan