I often use CTRL+R key to hide/show the result window, also use F7 & F8 keys to view the Object Explorer Details, Recently it stopped working after Microsoft windows Updates.
Whenever I hit "CTRL+R", The status bar says..."(Ctrl+R) was pressed. Waiting for the second key of chord..." as shown in the exhibit below
After followed below steps, the Key Functionalities are re-enabled
In SQL Server Management Studio,
1. Open the Tools menu,Options...
2. Under the Environment node click on the Keyboard node
3. Click the Reset button
4. Click Yes on the dialog that pops up
This step will solve your issue. Hope This Help!