NEED HELP!!It showed INSTALL PROBLEM when i want to lock in. How should i solve it?

It still functioning well when i used it last nite i am very sure that i quick it properly. But today when i on my pc it showed "INSTALL PROBLEM" ar the top of right hand site corner. It is like that:
The configuration defaults for Gnome Power Manager have not been installed correctly. Please contact your computer administrator.

At the same time, at the to top of left hand site corner it said that:
An error occurred while loading or saving configuration information for evolution-alarm-notify. Some of your configurations setting may not work properly.

That all it show out when i on my laktop and not even have the chance to type my password and get into the system yet.
So what i going to do to fix this problem as i am totally new in Ubuntu 10.04. I am fresh user. I love the simple and speed of Ubuntu and dont want to change to window now.

Please help me on this problem if you guys know how to fix this. Thanks so much.