Could not find build tools necessary . Facing error with devtools

问题

I am trying to install pacakage BTYDPlus (https://github.com/mplatzer/BTYDplus)

When I enter this command

devtools::install_github("mplatzer/BTYDplus", dependencies=TRUE)

It prompts me to install

Building R package from source requires installation of additional build tools. Do you want to install the additional tools now ? 

So, I went ahead and installed. I can see a folder RbuildTools in my C drive now. However

find r_tools() 
#returns TRUE

However when I try to install using Devtools , I get the same error again. I also tried assigning the path of build tools as per some suggestions but even that doesn't work

Sys.setenv(PATH="%PATH%;C:\\RBuildTools\\3.2\\gcc-4.6.3\\bin;C:\\RBuildTools\\3.2\\bin") 

来源：https://stackoverflow.com/questions/36002510/could-not-find-build-tools-necessary-facing-error-with-devtools