Sharyn, If the problem seems to be specific to certain packet sizes (e.g., the small mail body transmits without problems, but the large mail attachments, such as images, transmit with problems), then there MAY be a problem with MTUsize and/or blocking of certain ICMP types (e.g., 3 Destination Unreachable).
If two routers connect, packets may be sent up to the configured MTU size, if that size is too large, then the other router may require that the packet be fragmented and retransmitted - which can cause delays. If the ICMP 3 is not allowed, the sending router may not be aware of the problem and certain size data may never succeed. This is a common problem with PPPoE, tunneled and other connections where additional encapsulation headers will "chip away" from the "net" amount of data that a packet can carry. Don't know if it applies in your case, but worth investigating. Best Regards, Andy From: "Sharyn Schmidt" <[EMAIL PROTECTED]> Subject: FW: [IMail Forum] Ridiculously slow download time with attachments Date: Wed, 26 Dec 2007 07:41:18 -0500 Reply-To: [email protected] This is a multi-part message in MIME format. Good morning and Happy Holidays to everyone!=20 I am experiencing some very odd behavior and having problems pinpointing = the issue.=20 I have a remote site that also is a virtual IMAIL domain = (ibrandsinc.com) that is experiencing ridiculously slow download times for attachments. This just started last week.=20 They are connected to our main site (where the mail server is located) = via a frame circuit. I have had Verizon take down and test the WAN line, it's fine. Browsing between sites, netmeeting, RDP and basic connectivity is fine. Access to email via webmail is fine. Download/receiving email with = no attachments is fine. The only issue seems to be email WITH attachments, and the only issue is receiving attachments, not sending. Everyone in that site is = experiencing this issue, not just 1 person. No changes to anything down there have = been made. I logged onto their server and set up two accounts for myself in Outlook Express. I sent myself an email with a 1.5 mb attachment to a floridadistillers.com address and an ibrandsinc.com address. I attempted = to download both attachments from the server down there (one email at a = time). It took about 7 mins to download 1.5 mbs. That's nuts. Something happened to change something last week. I have no idea what or even where to begin to troubleshoot this, except for the things I've = already done. Suggestions?=20 Thanks,=20 Sharyn=20 To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
