Comment # 2 on bug 1201092 from Benjamin Zeller

(In reply to Petr Mladek from comment #0)
> I wanted to update mutt to the last version from the devel project
> 
>     zypper as -f
> https://download.opensuse.org/repositories/server:/mail/15.4/ server:mail

you are adding a service here, maybe that is the issue.
I guess you wanted to use `zypper ar`

> 
> Since then every zypper command fails with:
> 
>   root> zypper se less
>   Refreshing service 'server:mail'.
>   Problem retrieving the repository index file for service 'server:mail':
>   File './repo/repoindex.xml' not found on medium
> 'https://download.opensuse.org/repositories/server:/mail/15.4/?cookies=0'
>   Check if the URI is valid and accessible.
>   Segmentation fault (core dumped)

Here it tries to refresh a service not a repo.

> 
> I tried to remove the repository but it failed:
> 
>   root> zypper rr server:mail
>   Repository 'server:mail' not found by alias, number or URI.

Here you switched to the repo command instead of the service:
> zypper rr --help
> removerepo (rr) [OPTIONS] <ALIAS|#|URI>
>
> Remove repository specified by alias, number or URI.

vs 
> zypper rs --help                 
> removeservice (rs) [OPTIONS] <ALIAS|#|URI>
>
> Remove specified repository index service from the system.

Try using > zypper rs server:mail

> And the repository is not listed:
> 
> root@alley:/var/log> zypper lr

Same here, you are using the repo command, not the service command.

I will check next week why this is segfaulting, but try removing the service
and add it as a repository instead:

> zypper rs server:mail
> zypper ar -f https://download.opensuse.org/repositories/server:/mail/15.4/ server:mail
> zypper ref server:mail