Conference chefs::ms-exchange

868.0. "Client hangs with Netrider" by WOTVAX::WILLOUGHBYD (The man with no personal name) Fri Feb 07 1997 14:19

    I wonder if anyone can help me understand a wierd problem I am seeing
    with Exchange.  I'll try and keep this short but there's quite alot to
    explain. 
    
    The problem is trying to get the client to access the server over a
    dial-up connection using only TCP/IP.
    
    The server is v4.0 SP3. The client is v4.0 and the dial-up connection
    uses Digital Remote Network Access Server (or Netrider as it used to
    be called). Authentication is still done by the NT Server via the network, 
    but doesn't use RAS.
    
    This configuration is working quite happily in-house, but we are
    having difficulty getting it working at a customer site. Exchange works
    over the LAN but is a little slow (perhaps the 'Exchange providers' 
    setting will fix that).
    
    The dial-up to the server is successful and browsing all the network 
    shares works okay. However, when Exchange starts you can see modem 
    activity for about a minute or two then the client hangs. I used Network 
    Monitor (traces available on request), and the client and server are 
    clearly exchanging RPC requests, until after about 60 packets when 
    activity stops.
    
    Once the client is in this state I can still access the server via
    Network Neighbourhood and get at all the shares. Eventually, the task
    list has to be used to kill Exchange client. 
    
    Now the wierd part. If I go into Inbox properties and modify any of the
    Exchange Server Service properties - in fact I don't even need to
    actually change a value I just click OK - then try and start the
    client, it goes in without any problem. Once I exit again, then try and
    go back in, it hangs once more. This happens on all remote clients,
    different hardware, different client kits. The same clients can access
    another server at a different office.
    
    The name resolution is done by WINS. If the client is configured to use
    a DNS server (located at an external service provider) it works okay.
    We also configured the dial-in to use IPX, and that seems to work but
    it's very slow - at least we now have a workaround.
    
    Also if I turn on logging on the server, it looks like the client is
    being connected and logged on to Exchange, so the failure may be
    further into the conversation and therefore may point away from a name
    resolution issue.
    
    I've recently noticed that when it successfully connects, it may
    not be as good as it appears, I have tried accessing the Inbox once it
    connects and I'm pretty sure it hangs then - I haven't tested that
    enough yet t say for certain.
            
    I've tweaked the "Exchange Provider" registry settings and it doesn't
    seem to help (BTW when I use IPX I have to use NCACN_NP. NCACN_SPX
    doesn't work ? Anyone explain ?)
    
    Is there some kind of debugging client which would allow me to see the
    client/server conversation and get a better idea of what it's doing
    when it hangs ? Network Monitor doesn't give any clues as to what's in
    the RPC - I guess it may be encrypted anyway.
    
    Any ideas greatly appreciated. The customer is not at all happy and
    since they do all the buying of products and services for local
    authorities, it probably isn't doing us any good either.
    
    Thanks,
    
    Dave Willoughby