To restore the default settings for rollover tooltips
- Click Tools
tab
Customization
panel User
Interface. 
At the command prompt,
enter cui. - In the Customize User Interface Editor, Customize tab, in the Customizations In <file name> pane, right-click Rollover Tooltips.
- Click
Restore Default.
- Click
Restore the Default Rollover Tooltips Settings.
- Click Apply.