[Rd] R CMD check fails with: During startup - Warning message: Setting LC_CTYPE=en_US.UTF-8 failed

[Witold E Wolski]

Hello,

I am trying to run a package check on windows 10.
But it fails with the following errors:

```
$ R CMD check prolfqua_0.1.5.3.tar.gz
During startup - Warning message:
Setting LC_CTYPE=en_US.UTF-8 failed
* using log directory 'C:/Users/wewol/__checkout/prolfqua.Rcheck'
* using R version 4.0.3 (2020-10-10)
* using platform: x86_64-w64-mingw32 (64-bit)
* using session charset: ASCII
....
* checking DESCRIPTION meta-information ... WARNING
During startup - Warning message:
Setting LC_CTYPE=en_US.UTF-8 failed
 ERROR
During startup - Warning message:
Setting LC_CTYPE=en_US.UTF-8 failed
* DONE

Status: 1 ERROR, 1 WARNING, 3 NOTEs
See
  'C:/Users/wewol/__checkout/prolfqua.Rcheck/00check.log'
for details.
```

I am puzzled. I did a web search but all I found is:
https://stackoverflow.com/questions/54102869/during-startup-warning-message-setting-lc-ctype-failed-on-windows

I am reluctant to use .Rprofiles because otherwise, my R installation
works just fine.

Best regards
Witek


-- 
Witold Eryk Wolski