I lost the icon from yahoo on my desktop and don't know how to put it back on the desktop.?

go to the Yahoo home page.

http://ca.yahoo.com/?p=us

Click file top left on your desk top scroll down click send then click shortcut to desk top.

You are going to have to clarify what icon. Is it for messenger or a website?

To place an icon for any web site on the desktop do the following.

Go to the website.

Drag the icon that is just to the left of the URL to the desktop. On this page it is a green balloon with a white asterisk in it. You may have to make the window smaller to see the desktop.

Rename the Icon as desired.

For the messenger program find it in the start menu. Right click and "send to ... desktop".

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Go to Start, Programs and look for the Yahoo program from there. Once you find it, hold down the Control key and click once on the program and drag it to your desktop. Now you have a shortcut on your desktop to your program on Yahoo.