Do you know the specifications of your computer, such as processor speed, amount of memory and type of operating system (XP - Vista) How much spare disk space do you have? To find out, click on the 'My Computer' shortcut in the Start Menu. Right-click on the Local Disk (C:) icon and choose 'Properties' in the menu. A pie-chart will show how much disk space is used and how much is free.
Whether there is low disk space or not, a cleanup won't hurt. Click the Start button and then click Run. Type
cleanmgr in the box and click OK. This will open another box showing the drive letter (C:). Click OK. Windows will analyse the hard disk and then give a list of files that can be deleted.
Also, how many background programs do you have running? Background programs often show as icons next to the clock. Some can be safely prevented from starting and thus from perhaps taking up computer resources. How many icons do you have next to the clock?
Scan the computer disk with whatever arsenal of security software is installed, just to be on the safe side.
Sorry for all the questions

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