TCP/IP has detected high memory utilization and has terminated some existing connections to maintain system stability.

Please specify the OS and any other errors if listed in the event viwer.  Additionally, use the process explorer and observe/ monitor the performace, post your findings and as much as detail here.

OS is windows 2008 IIS 7.0 all .Net framework.

Log Name:      System
Source:        Tcpip
Date:          1/1/2010 4:48:35 PM
Event ID:      4201
Task Category: None
Level:         Information
Keywords:      Classic
User:          N/A
Computer:      iis****
Description:
The system detected that network adapter Loopback Pseudo-Interface 1 was connected to the network, and has initiated normal operation.

Log Name:      System
Source:        Tcpip
Date:          12/25/2009 12:16:57 PM
Event ID:      4227
Task Category: None
Level:         Warning
Keywords:      Classic
User:          N/A
Computer:      iis****
Description:
TCP/IP failed to establish an outgoing connection because the selected local endpoint was recently used to connect to the same remote endpoint. This error typically occurs when outgoing connections are opened and closed at a high rate, causing all available local ports to be used and forcing TCP/IP to reuse a local port for an outgoing connection. To minimize the risk of data corruption, the TCP/IP standard requires a minimum time period to elapse between successive connections from a given local endpoint to a given remote endpoint.

Please see the attached only problem we are facing over port 80.


IIS.htm

Might be its a issue of port 80 TCP/IP Listener.......please suggest....

Might be i am on right track...

http://technet.microsoft.com/en-us/library/cc734995%28WS.10%29.aspx

Sadly this could be a web application problem that is only showing up when a lot of connections are established.  It might not be a TCP/IP error at all.

Can you tell me more about your web application?