I get 'Error: '\U' used without hex digits in character string starting ""C:\U"' when starting R

Question

I have the following problem when starting RStudio and when I try to compile a PDF from a .rnw format:

Error: '\U' used without hex digits in character string starting ""C:\U"

When starting RStudio or just R, this is what is inside my console:

R version 3.4.0 (2017-04-21) -- "You Stupid Darkness"
Copyright (C) 2017 The R Foundation for Statistical Computing
Platform: x86_64-w64-mingw32/x64 (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

Global .Rprofile loaded!

Error: '\U' used without hex digits in character string starting ""C:\U"

And this happens when I try to compile a PDF:

Global .Rprofile loaded!

Error: '\U' used without hex digits in character string starting ""C:\U"
Execution halted

This kind of appeared from one day to another, and I am not sure what has changed. I tried updating RStudio and my R version, but it did not help. I am running R on Windows.

How can I fix this issue?

Ahithophel

Re the answers: Does backslash need to be escaped or not? Some of the answers seem contradictory. Is there some context dependence? – Sumach

Answer 1

I was able to solve this after all:

I had a section inside my .Rprofile file (in Documents) with "\" instead of "/". So I now changed

# Set mainfolder for PACKAGE package
options(PACKAGE_MAINFOLDER="C:\Users\...")

to

# Set mainfolder for PACKAGE package
options(PACKAGE_MAINFOLDER="C:/Users/...")

and that did the trick.

Ahithophel

Answer 2

To make it work, just remove the C:\Users\edmar.campos.cardoso\Dropbox\ and replace all \ with / using the function setwd() to change the working directory in R.

Wrong way:

setwd('C:\Users\edmar.campos.cardoso\Dropbox\...')

Right way:

setwd('/Users/edmar.campos.cardoso/Dropbox/...')

Linseylinseywoolsey

Answer 3

You can use \\ instead of \. This allows skipping from some characters such as \n which is the end of the line or \t which is tab.

Otterburn

Answer 4

For importing files in R, replace the '\' with (two) '\'. Single '\' probably reads it as escape sequence and hence the file path error.

Levana

Answer 5

I simply change the slash for backslash in the route of the file.

Example:
this instruction trigger the error. setwd("C:/Users\name\Desktop\RStudio")

Instruction fix:

setwd("C:/Users/name/Desktop/RStudio")

Forwhy

Answer 6

Sorry for posting a second answer, but now I think this second answer might be a better solution for the problem (I used both solutions quite simultaneously before):

In the .Rprofile file in "C:\Users\myusername\Documents," I had the following content:

# LanguageServer Setup Start (do not change this chunk)
# to remove this, run languageserversetup::remove_from_rprofile
if (requireNamespace('languageserversetup', quietly = TRUE)) {
  options(langserver_library = 'C:\Users\myusername\Documents/languageserver-library')
  languageserversetup::languageserver_startup()
  unloadNamespace('languageserversetup')
}
# LanguageServer Setup End

So obviously, there were incorrect slashes in options(langserver_library = 'C:\Users\myusername\Documents/languageserver-library').

Check if your file has similar problems. If yes, you should replace \ with /.

Rang

Answer 7

When you copy a directory address from properties in Windows and use it in R this happens you should easily use / instead of \.

Holladay

Answer 8

I had the same problem. The source of the problem was similar to Trenton's. My libPath contained \ instead of /. I changed it with the following:

.libPaths("C:\Users\myusername\Documents\R")

Check your libPaths with

.libPaths()

Take good care that you use a folder for which you also have writing rights. Otherwise, you won't be able to install packages and will get a "Permission denied" error! Usually, you won't have writing rights in "C:/Users/myusername/another folder;" instead, your Documents folder is a good choice.

Rang

Answer 9

use file.edit(file.path("~", ".Rprofile")) to edit the correct Rprofile and make sure that the file path on windows is referenced either using double "\\" or "/". Once I found this command file.edit(file.path("~", ".Rprofile")), it took a sec to identify the issue and resolve the issue.

Sill

Answer 10

Open the CSV file and save as the file to your "My Documents". Then use this:

[MyData <- read.csv("Data.csv",header = TRUE)]

If it’s text, just change read.csv to read.text.

Septi

Answer 11

Use two backward slashes instead of one as the argument. That will help you get the output.

For example, like this:

data<-read.csv("C:\\Users\\Vamsi\\Downloads\\pressure.csv")

Instead of:

data<-read.csv("C:\Users\Vamsi\Downloads\pressure.csv")

Preceptive