.Net Polling stops intermittently on few selected servers only.

.Net Polling stops intermittently on few selected servers only.

Hello team,
 
We have few virtual server on which .Net service is running.
 
stats related to Physical & logical thred doesn.t appear in graph frm time to time.
 
In order to  resolve issue we always restart Appmanger service but this is not a permamnent workaround .can you give me direction about where should i look for the problem.
 
License Information
Product
Applications Manager 11
 
 
 
Host Name APPMGR
OS Type & Version Windows Server 2008 R2, 6.1
OS Version 64 Bit
Database Type Microsoft SQL Server
Working Directory C:\Program Files (x86)\ManageEngine\AppMan...
Start Time Jul 1, 2013 12:36 PM
Build Number 11040
Product Edition Professional Edition
Server Port 80
Installation Type Standalone   
Load Factor 0.0

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