Problem description:
From the right-click menu; selecting Share > Send to Email... results in the following error:
KIOExec - Unable to create io-slave. klauncher said: Unknown protocol 'mailto'.

Troubleshooting thus far:
1. Verified Evolution was set as the default email client from Settings > Personalization > Applications > Default Applications. It was set properly.
2. Changed default email to Thunderbird and attempted Send to Email. This worked.
3. Changed default back to Evolution and tried again. Same KIOExec error received.
4. Changed default to Other..., searched for Evolution and selected the resulting entry. A new item appeared in the pick list, but the same error was given.
5. Returned selection to original Evolution entry.
6. Used Muon to reinstall KIO and tried again. The same error was received.

I'm not sure what else to try at this point and was not able to find anything related in the forums. I do not know when this first started; as this was my first attempt at using the feature. In case it's strangely related; the only other outstanding issue on the computer at the moment is with the Built-In audio profile (reported in topic: viewtopic.php?f=289&t=169612)

Advanced thanks for any help!

Operating System: Kubuntu 20.10
KDE Plasma Version: 5.19.5
KDE Frameworks Version: 5.74.0
Qt Version: 5.14.2
Kernel Version: 5.8.0-36-generic
OS Type: 64-bit
Evolution Version: 3.38.1-1
KIO Verison: 5.74.1-0ubuntu1

Maybe it is simply the command to Evolution which is not set correctly, did you link directly to the folder where the executable is? You should normally get the necessary arguments when typing

Code: Select all

evolution --help

A look at the menu entry could also be helpful, right click on the Menu button -> Edit Applications and go to Evolution to see which argument is used there.

Thanks for responding.

I was aware that the KDE Menu Editor entry for Evolution uses 'evolution %U', but since the default applications selection window returns the same list of applications found in the menu, I assumed when I selected that item it would have the switch as well. I then tried to select the location (/usr/bin/evolution) specifically from the browse option; but there isn't a place to specify switches. I tried entering the switch anyway, but it didn't work. By pure accident I left my cursor over the filter field while reading another post, when a tooltip appeared. It mentioned commands could also be entered in this field. This was the break through. I entered 'evolution %U' clicked OK. There is a new entry pointing to the same desktop file (~/.local/share/applications/evolution.desktop), but now the Send via Email works!!!

Thunderbird also has a switch, but it works using the default entry, so I still don't understand why the built-in entry for Evolution does not work. Seems like this may be a bug or a place for improvement, but at least my problem is solved. Thank you very much for the guidance!!!