When I got my C6-01 a few months ago, I found the calendar not usable. My previous S60 phone always showed a screenful of upcoming events on the home screen. The Symbian^3 Calendar has no such function.
I was about to send the phone back, when I discovered the ComingNext app, which supplies the missing function and makes the calendar usable. So far, so good.
Now the "missing device object" bug hit me. The suggestion to reset the phone is no option for me. I have two dozen vital apps installed, I have a 32 Giga memory card full of business data, and I am on a foreign business trip for another few weeks. I have no technical means to rebuild the phone, apart from the fact that this would take three days or so.
Shit, after my IBM-OS/2 disaster 15 years ago, I swore, I'll never invest my time into a dying platform again. But I have obviously done the same mistake again.