Great, glad it's resolved for you Raghav Gururajan.

Closing this report given the issue is covered in more detail in #35267:
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=35267.

On Tue, 23 Apr 2019, Raghav Gururajan wrote:

> Hello Ben!
>
> Thank you! It works now ☺
>
> On Tue, 2019-04-23 at 14:59 +1000, Ben Sturmfels wrote:
>
>    *  Error verifying signature: Failed to execute  
>     gpg.  
>  *
> On Sat, 30 Mar 2019, Raghav Gururajan wrote:
>
> Hello Guix!
>
> When I click "Apply" at the last step of "Add Account Wizard", I am getting the error "The name org.gnome.evolution.dataserver.Sources5 was not provided by any .service files".
>
> This issue has been discussed further in #35267:
> https://debbugs.gnu.org/cgi/bugreport.cgi?bug=35267
>
> If you're running Guix System and GDM, the solution for now is to
> install evolution-data-server into your system packages with something
> like this in your operating system config:
>
>   (packages (append
>     (list evolution-data-server)
>     %base-packages))
>
> Regards,
> Ben