[CentOS] A problem

Hello every one

I am a new user of CentOS, I have installed "CentOS-5.8-i386" as a virtual
machine on VMware Workstation 9.0 for learning purposes.

There is a frequented problems, when I want to use "Add/Remove software", I
get this error message:

"another application is currently running which is accessing software
information."

I have tried to know what's the problem from seaching, but, without any
good answer.