ERROR cannot verify's certificate while trying to install


I am trying to download and fresh start with new Virtualmin installation on other server with no previously installed LAMP or LEMP - nothing, but I can’t download since wget gives an error:

wget -O\&key=xxxxxxxxxB; /bin/sh

--2021-04-29 09:25:57--
Resolving (
Connecting to (||:443... connected.
ERROR: cannot verify's certificate, issued by ‘CN=R3,O=Let's Encrypt,C=US’:
  Unable to locally verify the issuer's authority.
To connect to insecurely, use `--no-check-certificate'.

I then used `–no-check-certificate’ and downloaded it but when I try to install Virtualmin with: sh ./ I get this error:

ERROR: cannot verify’s certificate, issued by ‘CN=R3,O=Let’s Encrypt,C=US’:
Unable to locally verify the issuer’s authority.
To connect to insecurely, use `–no-check-certificate’.
chmod: cannot access ‘’: No such file or directory
./ line 297: ./ No such file or directory

How to procced?

My solution was to temporary uninstall wget. Then the sh ./ started to install Virtualmin. But it didn’t go well. Installation ends with error. :thinking:
I will post it in another topic.

You don’t have the root cert for Let’s Encrypt on your system for reasons I can only guess. That’s a broken system, I assume, because it can’t make any https requests.

Do you have the ca-certificates package installed (I assume it is still called that). If not, you should. No system should ever not have it, and it should be almost impossible to end up without it.

You have somehow completely destroyed your Ubuntu install. Your best bet is to format the drive and start over. Just install the barebones Ubuntu 20.04 system. Do not add anything at all. Then download the installer for Virtualmin and launch it.

The entire thing should take no more than an hour and a half and you’ll have a system set up and running properly.

1 Like

I wouldn’t call it destroyed. It seems to just be missing the root certificate bundle (whatever provides that on ubuntu, I was thinking of centos above, so my suggested package name is probably wrong). But, I do have to say I can’t figure out how you could get a working/complete install of the OS without that bundle being installed. So much depends on it, it’s not normal to not have it.

Dear @Joe and @Gomez_Adams

I just reinstalled Ubuntu LTS and installed Virtualmin with a success.

Thank you for your suggestions and help.

Kind regards

1 Like

I tried and reinstall ca-certificates but even after there was still a problem so I decided to fresh install Ubuntu. Now it is OK.

This topic was automatically closed 8 days after the last reply. New replies are no longer allowed.