Hi and welcome to TSF. The first thing I would try is reinstalling the keyboard through device manager. As you are using Windows 98, support is limited through Toshiba and Microsoft, for they have abandoned further updates. Right click on my computer and click Properties. Click the Device Manager tab and look at the keyboard section. If there are any yellow conflict alerts (or if there aren't), right click the keyboard and click uninstall. Restart the PC and check it. Next, this could be hardware. below the keyboard, there should be a snap off flap. Remove it and remove the single screw securing the metal plate. The keyboard should now come out. Detach the keyboard cable by lifting the connector lock and tugging the cable. Attach it again by keeping the lock open and inserting the cable. Press down on the lock. Report back with details