Google provides a tool to sync Google Apps data with Microsoft Outlook.
   This tool syncs Mails,Contacts, Calendars and Task between Google Apps account and Microsoft outlook. 
   This a two way sync tool.

   If you are using this tool for syncing and if the tool is going offline regularly 
   follow the following steps to resolve this issue.

   This problem is mainly caused by the disturbance or issues in the network.
   And secondly because of antivirus installed in the system which restricts the behaviour of the Tool.
   For Outlook versions below Microsoft Outlook 2010 you only need to disable the antivirus and check.

   For Microsoft Outlook 2010 follow the steps given below:

Step 1: Open Outlook and goto File Menu and click Options.

Step 2: It will open Outlook Options dialog from the left sidebar click Add-ins.

Step 4: From main window, select an add-in from bottom of window and click Go

Step 5: Uncchecck the Antivirus add-ins andd click Ok.

Step 6: Now restart the Outlook and you will find it working properly.