SMTP-eMail upload very, very slow. MTU, RWIN, Latency adjustments?

[Peter Waibel]

I am connected over a 2000 Mbit/s DSL connection to my provider.

Down+Upload through ftp is no problem.
Surfing with browser is no problem
Downloading large emails with POP3 is no problem.

The only problem I have is "uploading" of eMails through SMTP.

The first 20KB-40KB are transfered quickly. But then it seems to me that the bytes are
transferring as single units. If an eMail is larger than approx 140 KB
then the SMTP upload is interrupted after half an hour.

This is independent from the target mailbox hence not an error of the provider.

This problem appears after my recent "upgrade" (re-installation) from Win2000
to WinXP.

Maybe I have to adjust the DSL IP settings MTU, RWIn or internal buffer size ?

Is there a tool which can check if this is a problem ?

Peter

 

[Ricky]

You can go here.. http://www.dslreports.com/tools and run the tweak test and
see if it might help.

 

[Guest]

I would doubt if this is a problem with your settigns, more likely a naff
service.

Standard MTU/RWIN settings tend to be on the conservative side and so are
unlikely to give trouble. It's when MTU is set to an excessive value, usually
by an overethusiastic tweaker, that you get problems.

 

[Ricky]

You can go here and run the tweak test to see if anything needs to be done..
http://www.dslreports.com/tools