# Sneaky errors that might occur when developing a problem set

• Problem: When running create.ps the following error message appears

Error in nchar(paste0(code, collapse = "\n")) :
invalid multibyte string, element 1
• Answer: This is a nasty error that has to do with the encoding of your text file. Try the following with your _sol.Rmd file. In RStudio choose the menu File -> Reopen with encoding. Then pick the Encoding UTF-8 and press ok. Now make some small changes in your file, save it and try again to run create.ps. Hopefully it now works…
• Problem: After changing the _sol.Rmd file and runing create.ps and show.ps, the browser opens but the changes do not appear in the shown problem set.

• Answer: Make sure that you have correctly set the working directory with setwd to the folder in which your _sol.Rmd file is stored.