Rcmdr problems: Dataset is not shown

I am having an error message that I don’t quite understand (I’m a fairly new to R).

There seem to be other related questions, but none seems to answer my question (at least, as far as I understand).

I uploaded a dataset using Rcmdr and got the normal message

exp <- read.table("D:/experiment/data per r- AMENDED - no NA.csv", header=TRUE, sep=",", na.strings="NA", dec=".", strip.white=TRUE)

So far so good. But, when I click on “View DataSet”, the dataset is not shown and I get the following messages:

On the Rcmdr window

library(relimp, pos=14)

on the main R

Error in if (packageAvailable("relimp") && ncols <= getRcmdr("showData.threshold")) { : missing value where TRUE/FALSE needed

Now, some discussions seem to suggest that it is because there might be some NAs, but I’ve got no missing data

The weird thing is that if I use the command to show my data set, it is shown.

Questions:

Is there something wrong with my dataset?

How Do I solve this problem?

What does ") && ncols <= getRcmdr("showData.threshold")) mean?

Thank you