If you live in a non-English locale such as I do, you’ll likely receive error messages in your locale language when things go wrong in R.

1 + "r"

## Error in 1 + "r": nicht-numerisches Argument für binären Operator

This is a problem because it highly limits the results when searching for error messages on Google. Have you ever read a stackoverflow post that was not in English? I haven’t.

So, how can you tell R to not translate error messages? By telling R that you are in an English locale.

Sys.setenv(lang = "en_US")

Your next error will be printed in English.

1 + "r"

## Error in 1 + "r": non-numeric argument to binary operator

Great!

The only problem with this approach is that the next time you start a new R session this change will be reverted. To make this change persistent add Sys.setenv(lang = "en_US") to your .Rprofile file.

Never heard of .Rprofile? It’s basically an R script that – if present – gets executed whenever you start R. That makes it perfect for the purpose of changing your locale.