R version 3.4.4 can't install packages

[New1997]

Hi,
Currently I can't install any package despite every solution out there
here is the error

Warning: unable to access index for repository https://cloud.r-project.org/src/contrib: cannot open URL 'https://cloud.r-project.org/src/contrib/PACKAGES'

i thought it might be one of the two reason (or none at all):

1. R can't get through proxy (my school use proxy and I prefer R in linux (ubuntu 18.04))
   or
2. the address https://cloud.r-project.org/src/contrib: .Please take notice that the address ends with ":" here, it might be the wrong address that R tried to connect to, hence the reason R can't connect to the repository (yesterday I was able to download a package but today I can't anymore)
   or it might be other reasons that I am not aware of (I have tried option(repos="https://cran.rstudio.com/") it doesn't work, I manually access those address in the web browser and both works but just not in R)

by the way I am using
R version 3.4.4 (2018-03-15) -- "Someone to Lean On"
Copyright (C) 2018 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

[jcblum]

Hi @New1997! Welcome!

@New1997

R can't get through proxy (my school use proxy and I prefer R in linux (ubuntu 18.04))
or

This is the most common reason for the error you’re seeing (when people can otherwise reach CRAN in a web browser). This might be helpful: https://support.rstudio.com/hc/en-us/articles/200488488-Configuring-R-to-Use-an-HTTP-or-HTTPS-Proxy

@New1997

Please take notice that the address ends with " : " here,

I can understand why you might be concerned because the syntax is a little unclear, but no need to worry about this! The : is not part of the URL that R tried to access. It’s just a separator between the headline and detail parts of the error message.

[New1997]

Hi,
Thank you for all your replies, now I just discover another problem:
R studio connects and download packages without any issues but R in cli still have the same error.
Regards

[EconomiCurtis]

On the "R can't get through proxy" theory"; If you think your university's internet is preventing you from allowing R to connect to CRAN, you might check with your university's IT folks first. I used to teach an R class in a university computer lab that prevented access to CRAN, (which makes teaching with R quite painful). I got a professor to put in a ticket to whitelist the repos install.packages() was connecting to, and all was good by the next class.

[New1997]

@jcblum
i tried with my personnal network (so no proxy) Rstudio works fine installation went fine but.... the R in the command line still can't connect to the repository, I still don't know why
Thanks

[technocrat]

You might try changing the repository from the regular R console, which should carry over to the CLI interface.

[jcblum]

You might also try some of the troubleshooting steps and/or workarounds mentioned in this thread:

Unable to install R packages -internet connection failures?

Dear all, I know similar qquestions have been asked before but all the suggested solutions I read about and that worked for other users failed in my case... I was suddenly no longer able to install R packages on my R version 3.3. and received the following error messsage: Warning in install.packages : unable to access index for repository http://cran.univ-paris1.fr src/contrib: cannot open URL 'http://cran.univ-paris1.fr/src/contrib/PACKAGES' Warning in install.packages I already tried several different mirrors which did not work. I even updated my R to the newest version (3.5.1) which also did not help. I changed the general options and unselected "secure download meth…

I'm afraid we're getting into the territory that gets very difficult to debug remotely, since there are many things specific to your system and your computing environment that could be involved.