Don't confuse the Memory with the C: drive.
Memory refers to RAM, C: drive is Storage.
Just reboot your phone, these things happen from time to time. That should get rid of the warning errors. This was common on the N97 up until recently - seems to have improved with the last firmware update.
Hope that helps.
1 . Yes Yes, Flash your phone, then:
2. Before you load your mail on to your phone - change the message store location to 'mass storage' or you are going to hit the same issue again.
Actually I did that unfortunately the pushmail program doesn't allow me to install it in mass memory. Any other way to cope with this.
By the way, how to hard reset, I can't find the icon?