[quote user="Thomas R. Stephenson"]>

You might want to get a copy of SG TCP Optimizer that I find quite handy.  http://www.speedguide.net/downloads.php  This little utility will allow you to test your MTU for maximum size without fragmentation against specific servers.  If will also make it easy to adjust the MTU.  
[/quote]

I ran it and it recommended I set my MTU to 1500, which I did. Apparently, it was not set (the box was blank when "Current Settings" was selected. I'll use Pmail some more and see if there is a change in behavior.

[quote user="Thomas R. Stephenson"]>

And finally, does this computer, by chance, happen to have an NVidia NForce 4 chipset on the motherboard?  If so, many other have had this exact problem, and it turned out to be an optimization setting for the built in NIC which caused the problems with packet fragmentation. Disabling the advanced optimization capability called "checksum offload" made all the problems of sending SMTP mail via WinPMail disappear.
[/quote]

 I have an NVidia NForce 2.

 Thank you so very much for your reply. It's given me a new avenue of actions to try.

Dave
 

I'm using Pmail 4.41 on Win XP SP2. For the last few months this problem has been getting worse. I'll reply to a message and it times out with the following errors:

[*] Connection established to xxx.xx.xx.xxx

>> 0071 220 mgr1.xmission.com ESMTP Exim 4.50 Thu, 07 Feb 2008 11:27:52 -0700

<< 0017 EHLO [10.0.0.2]

>> 0071 250-mgr1.xxxxxx.com Hello xxxxxxx.dsl.xxxxxxx.com [xxx.xxx.xxx.xxx]

>> 0019 250-SIZE 52428800

>> 0016 250-PIPELINING

>> 0014 250-STARTTLS

>> 0010 250 HELP

<< 0044 MAIL FROM:<me@isp.com> SIZE=673

>> 0008 250 OK

<< 0033 RCPT TO:<someone@whereever.org>

>> 0014 250 Accepted

<< 0029 RCPT TO:<someoneelse@whereever.org>

>> 0014 250 Accepted

<< 0006 DATA

>> 0056 354 Enter message, ending with "." on a line by itself

8: Socket read timeout.

<< 0006 RSET

8: Socket read timeout.

(The names have been changed to protect the innocent).

This is really driving me nuts 'cause it doesn't happen all the time, but more and more lately. I'm even thinking about switching email clients. This doesn't happen in Thunderbird.

 Any help would be greatly appreciated.

Dave
 

>
> I'm using Pmail 4.41 on Win XP SP2. For the last few months
> this problem has been getting worse. I'll reply to a message
> and it times out with the following errors:
>
> Connection established to xxx.xx.xx.xxx
> >> 0071 220 mgr1.xmission.com ESMTP Exim 4.50 Thu, 07 Feb 2008 11:27:52 -0700
> << 0017 EHLO [10.0.0.2]
> >> 0071 250-mgr1.xxxxxx.com Hello xxxxxxx.dsl.xxxxxxx.com [xxx.xxx.xxx.xxx]
> >> 0019 250-SIZE 52428800
> >> 0016 250-PIPELINING
> >> 0014 250-STARTTLS
> >> 0010 250 HELP
> << 0044 MAIL FROM:<me@isp.com> SIZE=673
> >> 0008 250 OK
> << 0033 RCPT TO:<someone@whereever.org>
> >> 0014 250 Accepted
> << 0029 RCPT TO:<someoneelse@whereever.org>
> >> 0014 250 Accepted
> << 0006 DATA
> >> 0056 354 Enter message, ending with "." on a line by itself
> 8: Socket read timeout.
> << 0006 RSET
> 8: Socket read timeout.
>
> (The names have been changed to protect the innocent).
>
> This is really driving me nuts 'cause it doesn't happen all
> the time, but more and more lately. I'm even thinking about
> switching email clients. This doesn't happen in Thunderbird.
>
>  Any help would be greatly appreciated.

Either your SMTP timeout setting is too low or more likely you have a packet fragmentation problem.  The POP3/SMTP transmissions may fail if the MTU packet size is so large that a packet is fragmented.  In many cases the receiving system router blocks the receiving servers "packets fragmented" response to the sending system using "MTU Discovery".  These oversize packets are not accepted and so are resent.  This results in a timeout, generally at the end of the message transmission but it can be anywhere in the process.  You need to reduce the MTU size. Windows defaults to a 1500 MTU and many routers and DSL connections need 1492.  You might simply want to turn off the MTU Discovery operation.

You might want to get a copy of SG TCP Optimizer that I find quite handy.  http://www.speedguide.net/downloads.php  This little utility will allow you to test your MTU for maximum size without fragmentation against specific servers.  If will also make it easy to adjust the MTU.  

And finally, does this computer, by chance, happen to have an NVidia NForce 4 chipset on the motherboard?  If so, many other have had this exact problem, and it turned out to be an optimization setting for the built in NIC which caused the problems with packet fragmentation. Disabling the advanced optimization capability called "checksum offload" made all the problems of sending SMTP mail via WinPMail disappear.


>
> Dave
>  
>