Since the keyboard works with 2 out of 3 accounts, you can probably rule out a defective keyboard. So that means there must be something about the 3rd account that isn't detecting the keyboard. While logged in to that 3rd account, try unplugging the keyboard, wait about a minute, then plug it back in to a different USB port. The Windows XP plug-n-play feature should detect the keyboard.
If not, try running the Add New Hardware Wizard. Click start > control panel > double click printers and faxes then follow the prompts.
Another possibility is to use the troubleshoot feature in Device Manager. Click start > run > type in DEVMGMT.MSC > OK. The device manager dialog box opens. Click the plus sign + next to keyboards. You should see the Dell keyboard listed. Double click on it. Another dialog box with several tabs should appear. On the general tab you have a troubleshoot button. On the driver tab you can check to make sure your computer has the latest driver installed.
http://www.experts-exchange.com/Hardware… >scroll to bottom of page
http://www.overclockers.com/articles1550… >moody keyboard
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