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Users lose connection to Exchange. RRS feed

  • Question

  • Hi

    I have a Exchange 2007 on Windows 2003 environment with  about 9,000 users.

    Lately I have been struggling with an issue and I need some help.

    Some users lose their connectivity of Outlook to Exchange (outlook appears Offline), even though they have Network connection and normally to solve this, I disconnect the network cable and reconnect it. I just want to clarify if this is a network or Exchange issue and also, how could I solve this.

    Thanks.

    Monday, August 11, 2014 10:09 AM

Answers

  • 1) If unplugging the network cable to the user's computer and plugging it back in again fixes the issue, it is probably not a, server issue.

    2) However, to test, can the user access OWA while their Outlook is unable to connect? If so, their mailbox is fine.

    3) How are you configuring Outlook to connect - RPC/TCP or RPC/HTTP (OutlookAnywhere)?  RPC/TCP will connect directly to the Mailbox server with Exchange 2007 and OutlookAnywhere will connect to the CAS server, so it is important to distinguish which connection you are troubleshooting.

    4) What is common about the group of users who lose connectivity? Same switch? Same Database? Connecting to same CAS (if OutlookAnywhere)?

    5) Do some basic network connectivity tests (ping, tracert, nslookup, etc) on the PC when in repro

    6) Collect and analyze a netmon capture during the issue.

    EDIT:

    Also, from a client perspective - take a look at event logs.   Also, is AV installed and does the issue occur if you uninstall or disable it temporarily?

    Monday, August 11, 2014 12:41 PM
  • If Outlook is configured to use RPC-over-HTTPS on "slow" connections it will try to use that means of connecting if the RPC/TCP connection is lost -- even if the interruption is only for a short duration.

    That switch to RPC/HTTP will, if the OWA site is configured for basic authentication, challenge the user for credentials. Sometimes that dialog box is hidden behind some other window.

    Instead of unplugging the network cable, I suppose the original poster could click on the "Reconnect" button while in the "Connection Status" dialog box. That might work without his having to visit the workstation.


    --- Rich Matheisen MCSE&I, Exchange MVP

    • Marked as answer by Niko.Cheng Monday, August 25, 2014 2:54 AM
    Monday, August 11, 2014 4:36 PM

All replies

  • Hi,

    Can you just try to reconfigure the outlook from the system which is showing outlook offline. If still you are getting the issue then re-create the user on exchange server then ask the user to access the mailbox.

    Monday, August 11, 2014 10:18 AM
  • Hi Sunil,

    So you mean, reconfigure the  user's Outlook profile and if it doesn't work, delete the user mailbox a re-create it?

    what about moving to another mailbox database? could that work?

    Monday, August 11, 2014 12:19 PM
  • 1) If unplugging the network cable to the user's computer and plugging it back in again fixes the issue, it is probably not a, server issue.

    2) However, to test, can the user access OWA while their Outlook is unable to connect? If so, their mailbox is fine.

    3) How are you configuring Outlook to connect - RPC/TCP or RPC/HTTP (OutlookAnywhere)?  RPC/TCP will connect directly to the Mailbox server with Exchange 2007 and OutlookAnywhere will connect to the CAS server, so it is important to distinguish which connection you are troubleshooting.

    4) What is common about the group of users who lose connectivity? Same switch? Same Database? Connecting to same CAS (if OutlookAnywhere)?

    5) Do some basic network connectivity tests (ping, tracert, nslookup, etc) on the PC when in repro

    6) Collect and analyze a netmon capture during the issue.

    EDIT:

    Also, from a client perspective - take a look at event logs.   Also, is AV installed and does the issue occur if you uninstall or disable it temporarily?

    Monday, August 11, 2014 12:41 PM
  • Hi brenle,

    Thanks for the input...

    All users have Outlook Anywhere settings enabled. Will that make the RPC/HTTP connect before RPC/TCP?

    All the other tips you gave, I'll test when the next case appears.

    thanks.

    Monday, August 11, 2014 1:41 PM
  • Unless configured to connect over fast and slow networks, RPC/HTTP will by default (Exchange 2007/2010) connect only over the internet (slow).

    To check whether the connection is RPC/TCP or TPC/HTTP, you can press CTRL and right click the Outlook icon in the system tray, then select "Connection Status".  Or you can simply open Outlook using the run command: "Outlook /rpcdiag"

    Monday, August 11, 2014 1:45 PM
  • If Outlook is configured to use RPC-over-HTTPS on "slow" connections it will try to use that means of connecting if the RPC/TCP connection is lost -- even if the interruption is only for a short duration.

    That switch to RPC/HTTP will, if the OWA site is configured for basic authentication, challenge the user for credentials. Sometimes that dialog box is hidden behind some other window.

    Instead of unplugging the network cable, I suppose the original poster could click on the "Reconnect" button while in the "Connection Status" dialog box. That might work without his having to visit the workstation.


    --- Rich Matheisen MCSE&I, Exchange MVP

    • Marked as answer by Niko.Cheng Monday, August 25, 2014 2:54 AM
    Monday, August 11, 2014 4:36 PM