Set max DLLs in R (Windows)

If you need to adjust the max number of .dll files that R can handle, here is code that works if you are using Windows.

On occasion, you may need adjust the max number of .dll files that R can handle. I first encountered this need when using a high number of packages together.

I’ve had trouble finding this info in the past, so I decided to create this post for others. This works if you are using Windows.

The following is machine-specific, so you will need to do this on each computer you run R.

Find the .Renviron file

user_renviron <- 
  path.expand(file.path("~", ".Renviron"))
# check to see if the file already exists
# typically under: "C:/Users/YOURUSERNAME/Documents/.Renviron"
if(!file.exists(user_renviron)) 
  file.create(user_renviron)
file.edit(user_renviron) 

If file.edit(user_renviron) fails to work, just open the file itself (located wherever user_renviron is pointing) with a text editor.

Edit max DLLs

Once you have the file open, edit or add the following line, save, and restart R:

R_MAX_NUM_DLLS=500

🐢