XCON: Client Cannot Retrieve Message in Parts Using SSL |
The information in this article applies to:
-
Microsoft Exchange Server, version 5.5
SYMPTOMS
IMAP4 customers using Netscape Messenger 4.5 enabled for Secure Socket
Layer (SSL) against an Exchange Server 5.5 IMAP4rev1 computer, might
encounter message content loss. Messages 6 KB in size or greater might be
truncated (this is regardless if messages contain attachments or not).
CAUSE
Netscape Messenger 4.5 has moved to fetching messages in chunks (prior
releases of Messenger always fetched the entire message). The command
Messenger now issues to fetch a message is as follows:
11 UID fetch 320 (UID RFC822.SIZE BODY[]<0.6144>)
When using clear text, the server will respond to the above command with
exactly 6144 bytes of message data. When using SSL, Exchange Server can
return more than 6144 bytes of message data. When more bytes than requested
is received by Messenger, the client logs out without retrieving any more
message data. Hence, the message is displayed truncated.
RESOLUTION
To resolve this problem, obtain the latest service pack for Exchange Server
version 5.5. For more information, please see the following article in the
Microsoft Knowledge Base:
Q191014
XGEN: How to Obtain the Latest Exchange Server 5.5 Service Pack
The English version of this fix should have the following file attributes
or later:
Component: Information Store
File Name Version
-----------------------
Gapi32.dll 5.5.2437.0
Mdbmsg.dll 5.5.2437.0
Netif.dll 5.5.2437.0
Store.exe 5.5.2437.0
WORKAROUND
The obvious work around is to turn off SSL with Netscape 4.5. For customers
who need to continue using SSL with Netscape Messenger 4.5, a client
configuration change can be made which will alleviate the problem.
When added to the Netscape user Pref.js file, the following line will turn
off fetching in chunks:
user_pref("mail.imap.fetch_by_chunks", false);
Netscape Messenger 4.5 will return to fetching the entire message in one
command (as was the behavior in Netscape Messenger 4.07). Upon restarting
the client, messages that were previously truncated can be fetched again
and all message content displayed.
STATUS
Microsoft has confirmed this to be a problem in Microsoft Exchange Server
version 5.5. We are currently working on a fix to correct this problem.
Keywords : exc55sp2fix
Version : WinNT:5.5
Platform : winnt
Issue type : kbbug