I'm currently running on Windows XP Home Edition..

If I want to temporaly disconnect my internet connection,it gives me a error message "It is not possible to disable the connection at this time. This connection may be using one or more protocols that do not support Plug-and-Play, or it may have been initiated by another user or the system account"

I got only one user account on this PC..

I could temp disconnect the internet previously, but all of a sudden it starts giving me that error message.What can be the problem?

Any changes that either happened or that you perhaps made to your computer around the time that the problem started; particularly any software or hardware that you installed or setup.

-You can try to do a system restore to go back when before this was happening
-Go down to the part of the webpage where you see
Use System Restore. And go from there

Windows XP System Restore Is Easy to Use (http://www.microsoft.com/windowsxp/using/helpandsupport/getstarted/ballew_03may19.mspx)