The final way to recover missing icons in Windows 7 is via the Group Policy Editor. Group Policy is used to specify user and computer configurations. You must be logged into the computer as an administrator to open the Group Policy Editor, and it is only available in Windows 7 Professional, Ultimate, and Enterpise editions. If you using Windows 7 Starter or Home Premium editions you will not have this option. To find out what version of Windows 7 you have, click the Start button, right-click Computer and select Properties. The version will be listed near the top of the main window under Windows Edition.
To open the Group Policy Editor, click the Start button, type gpedit.msc into the Instant Search box at the bottom of the Start menu and press Enter. (To find out more about Instant Search, read Searching for Folders in Windows 7.)

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Click Administrative Templates under User Configuration. Double-click Desktop. Double-click Remove Name Icon, where Name is the name of the location for which the icons is missing. For example, if the Recycle Bin icon is missing, double-click Remove Recycle Bin Icon. Click the Setting tab, click Not Configured, and then click OK. Repeat for each of your missing icons in Windows 7.