I have a problem to install package 'swirl' on my Rstudio. I tried several cran in China and it cannot connect to server every time. Does anyone know any possible reason? *ps:since the stackoverflow does not allow me to post more than one URL link so I cut off a 'h' of from 'http'
install.packages("swirl")
Warning in install.packages :
URL 'http://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib/PACKAGES.rds': status was 'Couldn't connect to server' Warning in install.packages : URL 'ttp://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib/PACKAGES.gz': status was 'Couldn't connect to server' Warning in install.packages : URL 'ttp://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib/PACKAGES': status was 'Couldn't connect to server' Warning in install.packages : unable to access index for repository ttp://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib: cannot open URL 'ttp://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib/PACKAGES' Warning in install.packages : URL 'ttp://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib/PACKAGES.rds': status was 'Couldn't connect to server' Warning in install.packages : URL 'ttp://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib/PACKAGES.gz': status was 'Couldn't connect to server' Warning in install.packages : URL 'ttp://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib/PACKAGES': status was 'Couldn't connect to server' Warning in install.packages : unable to access index for repository ttp://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib: cannot open URL 'ttp://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib/PACKAGES' Warning in install.packages : package 'swirl' is not available (for R version 3.4.0) Warning in install.packages : URL 'ttp://mirrors.tuna.tsinghua.edu.cn/CRAN/bin/macosx/el-capitan/contrib/3.4/PACKAGES.rds': status was 'Couldn't connect to server'
