SQL: Intellisense is not working

Given below are four different ways through which you can enable IntelliSense.

1) Make sure you are connected to SQL Server 2008 Edition. 
IntelliSense does not work with the previous versions of SQL Server.

2) IntelliSense should be enabled.There are two ways to verify whether IntelliSense is enabled or not.
a) From Toolbar

b) Go to Tools >> Options >> Text Editor >> Transact-SQL >> IntelliSense

3) IntelliSense should be refreshed with the latest changes in database. 
a) Press CTRL+SHIFT+R
b) Go to Edit >> IntelliSense >> Refresh Local Cache

4) Go to Tools >> Options >> Text Editor >> Transact-SQL >> General >> IntelliSense
Select Auto List Members and Check Parameter Information.

Troubleshooting:

• After all the above mentioned settings, If IntelliSense still does not work then try the following one more setting: Verify that the T-SQL Editor does not launch in SQLCMD mode Under Tools->Options->Query Execution->SQL Server->General, make sure “By default, open new queries in SQLCMD mode” is unchecked. 
• If your SQLCMD mode check box is already unchecked then mark it checked -> DONE -> then unchecked again and after reopening the New Query – window you will find the working Intellisense.