Restoring the missing or deleted Calculator in Windows XP

1) Right click on the Taskbar, (It is a bar at the bottom of your screen with Start button, Clock, etc) and select "Properties".
2) You will be displayed with a Window named "Taskbar and Start Menu Properties" that has two options a) Taskbar and b) Start Menu. Click on Start Menu.
3) Select "Classic Start Menu" option,
4) Then click on the "Customize" button,
5) Under "Start Menu" frame, click on "Add" button,
6) You will be displayed with "Create Shortcut" Window,
7) There you can see a white editable box and "Browse" button,
8) Click on "Browse" button, then you will displayed with "Browse for Folder" Window,
9) Click on the "+"button of "My Computer",
10) Click on the "+"button of "Local Disk (C:)",
11) Click on the "+"button of "Windows",
12) Click on the "+"button of "System32" folder,
13) Search for "calc" icon.
14) Finally click on "calc", Click on Ok button,
15) You will be taken back to "Create Shortcut" window, there you click on "Next" button,
16) You will be displayed with a new Window named "Select a Folder to place this shortcut in:",
17) There click on Accessories, (by doing this Calculator will be placed under Accessories)
18) You will be displayed with a new Window named "Select a Title for the Program", just click on Finish button,
19) Then again click on Ok button of the new Window.
20) Again click on Ok button on the new Window.

By following the above steps you will be able to restore Calculator back on to your Accessories.