[Ethereal-users] email attachment times out

["Jon Miller" <jlmiller@xxxxxxxxxxxxxxxxxx>]

Lately, I've been having an issue where my e-mail is timing out when I send an attachment.  Whereas if I send just an e-mail I do not have any issues.
I ran ethereal v0.10.13 to capture some packets and notice a great deal of retransmissions and checksum errors.  I've run previous versions of ethereal and never had any of these.  I read in the FAQ regarding checksum issues and I'm not sure this is generated because the packets are just handed over.  I've exported the packet capture in a plain text file at http://www.mmtnetworks.com.au/email-attachmt.txt.
Would appreciate any help on what the cause may be.

This workstation (Zen1) 192.168.1.143 connects to a 48-port Cisco switch 2950.

Thanks