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This more like windows/Networking than Exchange, have you tried NIC Driver and NIC Firmware?
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This more like windows/Networking than Exchange, have you tried NIC Driver and NIC Firmware?

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We deployed a batch of DL 380 G9 Exchange 2016/Windows 2012 R2 servers in a few sites. &nbsp;We're seeing the below error in the System Event Logs. &nbsp;Anyone familiar with the fix for this? The NICs are teamed. &nbsp;<br />
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TCP/IP has chosen to restrict the congestion window for several connections due to a network condition. &nbsp;This could be related to a problem in the TCP global or supplemental configuration and will cause &nbsp;degraded throughput. <br />
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Log Name: &nbsp; &nbsp; &nbsp;System<br />
Source: &nbsp; &nbsp; &nbsp; &nbsp;Tcpip<br />
Date: &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;3/16/2018 12:13:40 AM<br />
Event ID: &nbsp; &nbsp; &nbsp;4230<br />
Task Category: None<br />
Level: &nbsp; &nbsp; &nbsp; &nbsp; Warning<br />
Keywords: &nbsp; &nbsp; &nbsp;Classic<br />
User: &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;N/A<br />
Description:<br />
TCP/IP has chosen to restrict the congestion window for several connections due to a network condition. &nbsp;This could be related to a problem in the TCP global or supplemental configuration and will cause &nbsp;degraded throughput.
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We deployed a batch of DL 380 G9 Exchange 2016/Windows 2012 R2 servers in a few sites.  We're seeing the below error in the System Event Logs.  Anyone familiar with the fix for this? The NICs are teamed.  

TCP/IP has chosen to restrict the congestion window for several connections due to a network condition.  This could be related to a problem in the TCP global or supplemental configuration and will cause  degraded throughput. 

Log Name:      System
Source:        Tcpip
Date:          3/16/2018 12:13:40 AM
Event ID:      4230
Task Category: None
Level:         Warning
Keywords:      Classic
User:          N/A
Description:
TCP/IP has chosen to restrict the congestion window for several connections due to a network condition.  This could be related to a problem in the TCP global or supplemental configuration and will cause  degraded throughput.

Exchange 2016 Error in System Event Logs - TCP/IP has chosen to restrict the congestion window for several connections due to a network condition.

Exchange is the server side of a collaborative application product that is part of the Microsoft Server infrastructure. Exchange's major features include email, calendaring, contacts and tasks, support for mobile and web-based access to information, and support for data storage.

Exchange

Within Internet message handling services (MHS), a message transfer agent or mail transfer agent (MTA) or mail relay is software that transfers electronic mail messages from one computer to another using a client–server application architecture. A MTA implements both the client (sending) and server (receiving) portions of the Simple Mail Transfer Protocol (SMTP). The terms mail server, mail exchanger, and MX host may also refer to a computer performing the MTA function. The Domain Name System (DNS) associates a mail server to a domain with mail exchanger (MX) resource records containing the domain name of a host providing MTA services.

Email Servers

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