Have had several clients over the past three or four months report that their 3rd party CRMs are no longer able to send out email.

In all honesty I dismissed the first couple of complaints because didn't have a lot of complaints...  so my issues for not capturing this earlier..   and as to which release.

But here is the issue that I see

[2022.10.13] 07:20:57.886 [XXX.XXX.XX2.60][48811648] Exception: (PooledTcpItem.cs) Unable to read data from the transport connection: 

                            An established connection was aborted by the software in your host machine.

[2022.10.13] 07:20:57.886 [XXX.XXX.XX2.60][48811648] StackTrace:    at System.Net.Sockets.NetworkStream.BeginRead(Byte[] buffer, Int32 offset, Int32 size, AsyncCallback callback, Object state)

[2022.10.13]    at System.Net.FixedSizeReader.StartReading()   at System.Net.Security._SslStream.StartFrameHeader(Byte[] buffer, Int32 offset, Int32 count,

                 AsyncProtocolRequest asyncRequest)   at System.Net.Security._SslStream.StartReading(Byte[] buffer,

                 Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest)   

                    at System.Net.Security._SslStream.ProcessRead(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest)   at System.Net.Security._SslStream.BeginRead(Byte[] buffer, Int32 offset, Int32 count, AsyncCallback asyncCallback, Object asyncState)   at MailService.TcpServerLib.Common.PooledTcpItem.BeginReceive()

The two CRMs that have reported in the past couple of day are:

    VTiger -CRM

    Suite - CRM

Please note.. I did see these same two CRMs connect to gmail without fail.. (customers had me do a zoom to watch).  So I know it is on my side, just not sure how to resolve