Corrupted message stream

[JPSEP]

Messages from certain sites arrive corrupted - OE client cannot determine sender/subject/attachement.

Viewing 'message' via OE or in 'archive' shows browsing activity and occasional merging of 2 messages (not an OE problem).

Not definitive, but there also appears to be an SMTP Interface Event 4153 ...attempted to submit without using authentication... prior to each corrupted message.
Authentication is not required or set (no off-site access).

Problem is specific and consistent to about a dozen sites and can be worked around by bouncing mail through another site (set up another domain off site with mail forwarding addresses).

Configuration: Exchange 5.5 on NT4sp6a+ freshly installed with all patches, IMC connector only and no IIS etc. Gateway to internet (separate machine outside NT domain) uses WinProxy 5.1 (they are looking into problem - s l o w l y). WinProxy is suspect because only it knows about browsing activity and handles the message stream. Disabling their A/V had no effect.

Don't expect complete solution - but insight into SMTP Interface Event 4153 would be much appreciated.

Thanks.

 

[JPSEP]

Some more info...

This is related to problem when Exchange 2000 came out...
XEXCH50...354 Send Binary would not pass through firewall when Exchange2000 came out.

The sites with whom we have receipt problems are wanting XEXCH50 and are getting a 505 Authentication Required...

Unlike before, the message gets delivered but it is often (always from some sites) corrupted.

Issue appears to have arisen from Exchange patches and updates because firewall has not changed.

Last time the solution was to run smtp past the firewall (mapped port).

Seems options are: replace firewall with something more compatible than 'winproxy', upgrade/replace exchange (good until new version recreates problem), switch to non-exchange server and hope ms plays better with others than it does with itself.

Any thoughts?

 

[JPSEP]

Another option: disable advertising of XEXCH50 service in 5.5?

I believe it can be done on Exchange 2000 - does anyone know how for Exchange 5.5??