diff --git a/src/ts/@overflow/probe/react/components/ProbeDown.tsx b/src/ts/@overflow/probe/react/components/ProbeDown.tsx
index e5db489..38a2b5b 100644
--- a/src/ts/@overflow/probe/react/components/ProbeDown.tsx
+++ b/src/ts/@overflow/probe/react/components/ProbeDown.tsx
@@ -44,8 +44,9 @@ const osNames = [
 export class ProbeDown extends React.Component<any, any> {
   constructor(props: Props, context: State) {
     super(props, context);
-
-    this.state = { activeItem: osNames[0].name };
+    this.state = {
+      activeItem: '',
+    };
   }
 
   public handleItemClick = (event: React.SyntheticEvent<HTMLAnchorElement>, data: MenuItemProps): void => {
@@ -54,6 +55,9 @@ export class ProbeDown extends React.Component<any, any> {
 
   public ShowContent = (): JSX.Element => {
     let os = this.state.activeItem;
+    if(os === '') {
+      return <div>Instruction page.</div>;
+    }
     switch (os) {
       case 'Windows': {
         return <Windows />;
@@ -74,15 +78,14 @@ export class ProbeDown extends React.Component<any, any> {
   }
 
   public render(): JSX.Element {
-    const { activeItem } = this.state.activeItem;
     return (
       <Container fluid>
         <Grid>
           <Grid.Column width={4}>
-            <Menu fluid vertical icon='labeled'>
+            <Menu fluid vertical icon='labeled' pointing>
               {osNames.map((item: any, index: number) => {
                 return (
-                  <Menu.Item key={index} name={item.name} active={activeItem === item.name} onClick={this.handleItemClick} >
+                  <Menu.Item key={index} name={item.name} active={this.state.activeItem === item.name} onClick={this.handleItemClick} >
                     <Icon name={item.icon} />
                     {item.name}
                   </Menu.Item>