This is my first post, but I am so angry about this and I don't know how to solve it!
A while ago, I was attempting to use KAlarm to make an alarm that would shut down my computer at a certain time each day. I created an alarm with the terminal shutdown command "shutdown -h now", and since the alarm activates the command even when the reminder in a certain time thing is turned on, I configured the alarm so that it would activate the day after at 6 AM, would cancel any late instances if an hour has passed since, and I would set the alarm reminder for 8 hours beforehand. All went well for a while, but afterwards, whenever I launched KAlarm again, it just shuts my computer down again!

Even after uninstalling and re-installing the application, the "shutdown -h now" command is still there and activates automatically every time I launch KAlarm!!!

After using KShutdown as my shutdown application, I really want to use KAlarm again just so I could have an opportunity to make other related alarms. But just because I made that awful alarm on my installation, I cannot use KAlarm in general anymore because even after completely reinstalling the application and its dependencies, every time I launch KAlarm again, my computer would just shut down immediately after!

How do I fix this without launching KAlarm?!?!

Which version of KDE are you using - 4 or 5?

If you are using kde 4, kalarm has a config file at ~/.kde/share/config/kalarmrc, and a config directory at ~/.kde/share/apps/kalarm.
If you are using kde 5, the config folder should be under ~/.config/kalarm.

You may confirm that the shutdown command is listed in one of the .ics files. Those directories may be deleted without problems.

I actually completely forgot I made this thread! I asked the same question in the Manjaro forums and was told to go to ~/.local/share and delete the kalarm folder. Here is what I said on that forum in the end:

I deleted the WHOLE folder, uninstalled KAlarm, rebooted, and reinstalled KAlarm, and other than the window bar nonexistent because I'm in a GTK environment (Same thing with KShutdown), the problem is fixed!!!