I can't install any package in R studio

when i try to install any package appear this massage

Warning in install.packages :
unable to translate 'C:/Users/<U+0627><U+0644><U+0644><U+0647> <U+0627><U+0643><U+0628><U+0631>/Documents/R/win-library/4.1' to native encoding
Error in install.packages : unable to translate 'C:\Users<U+0627><U+0644><U+0644><U+0647> <U+0627><U+0643><U+0628><U+0631>\Documents\R\win-library\4.1' to native encoding

how can i solve this problem
Note that my windows 8.1

R has problems with non-ASCII characters in your Windows user name, try setting your package library in a different location.

You can change the default library folder by setting your R_LIBS_SITE environmental variable in a .Reviron or .Rprofile file. For example:

# In a .Renviron file you can set it by adding a line like this one with the desired location 
R_LIBS_SITE="C:\\Program Files\\R\\R-4.1.2\\library"

For a more detailed explanation, you can read this blog post