Tommy O'Dell Tommy O'Dell - 5 months ago 30
R Question

devtools::install_github() - Ignore SSL cert verification failure

I'm trying to get

working behind my corporate proxy on Windows 7.

So far I've had to do the following:

> library(httr)
> library(devtools)
> set_config(use_proxy("",8080))
> devtools::install_github("rstudio/ggvis")

Installing github repo ggvis/master from rstudio
Downloading from
Error in function (type, msg, asError = TRUE) :
SSL certificate problem, verify that the CA cert is OK. Details:
error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed

Apparently we have some kind of certificate server replacing SSL certs with our own corporate SSL certs (confirmed by going to and examining the cert).

Anyhow, just wondering if there's a way to ignore that cert error and proceed with the installation?


One way to handle the problem is to set the CURLOPT_SSL_VERIFYPEER to false. This option determines whether curl verifies the authenticity of the peer's certificate. A value of 1 means curl verifies; 0 (zero) means it doesn't.

The relevant option needs to be passed to RCurl. In RCurl the CURLOPT_ is removed letters arre lowercase and the underscore is changed to ..

set_config( config( ssl.verifypeer = 0L ) )

will pass the relevant option to RCurl when using httr.