How to troubleshoot WSUS client side issues.

First step you need to check is the communication between the WSUS server and client, there is a tool already available to check this.

You can download this tool from the following URL

http://download.microsoft.com/download/9/7/6/976d1084-d2fd-45a1-8c27-a467c768d8e
f/WSUS%20Client%20Diagnostic%20Tool.EXE

Command to manually pull update from WSUS Server

wuauclt /detectnow

Command to manually update status of the client to WSUS Server

wuauclt /reportnow

To check the Automatic Update related logs

C:\WINDOWS\SoftwareDistribution\reportingevents.logs