R help - Jan 2018 - using randomForest() with matrix() as input results to an Error: protect(): protection stack overflow

Hello,

I'm trying to figure out a solution online but couldn't so far. I
realized
that others dealt with such an error but their suggestions didn't work for
me.

So, I'm trying to run the randomForest() using this command:

rf = randomForest(classes~., data=as.matrix(train), mtry=5, ntree=2000,
importance=TRUE)

and it always results in *Error: protect(): protection stack overflow.*

As you can see, I have already turned the training dataset into a matrix
but this didn't fix anything.
> Cstack_info()
      size    current  direction eval_depth
   7969177      13104          1          2

I also tried the options(expressions = 12e4) but nothing really changed.

The PC I'm running this on has 12 GB RAM and runs on Linux.

The dim(train) returns: 50 20040.

Is there something else to try, or I should run it on a different PC?

Thanks.

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