Error 29114.Cannot connect to DB.

Dear:

I use EXSI5+ WIN 2008 R2 X64 +SQL 2012 X64

and use VMware-VIMSetup-all-5.1.0-947939.iso

First ,I want to  install "vCenter Single Sign On" on WIN2008 R2

But,I get message as "Error 29114.Cannot connect to DB."  in the finnaly,SO It was be rollback install

How can I  resolve it.

THX!