Troubleshooting slow startup of Outlook and Exchange clients

When you start the Microsoft Exchange client, one of the more common reasons for slow startup is the failure to resolve the Microsoft Exchange Server TCP/IP host name. This document discusses the steps for eliminating host name resolution issues on client computers with Transmission Control Protocol/Internet Protocol (TCP/IP) running. Start troubleshooting by going to the Microsoft Exchange Server properties of the user profile. With the correct server name and mailbox entered, click the Check Name button to get an idea of how much time it is taking to resolve the name. If the time to resolve is greater than 30 to 40 seconds, continue the troubleshooting steps in this article to help improve startup times.

In the Microsoft Exchange Server properties of the client profile, type the IP address instead of the server name, and then click Check Name. This will not only test name resolution, but also will do a basic RPCPING to the computer running Microsoft Exchange Server.

If the IP address fails to resolve to the correct Exchange Server name, there is either a problem with Remote Procedure Calls (RPCs) to the computer running Microsoft Exchange Server or a problem with the IP Address of the computer running Microsoft Exchange Server. If the IP address failed, perform the following steps:

1. At an MS-DOS prompt, try to ping the IP address of Exchange Server. If this fails, then there may be a networking issue or a TCP/IP configuration issue that is not allowing connection to the Exchange Server machine. This issue must be resolved before the Exchange client will be able to connect to the Exchange Server over TCP/IP.
2. If a ping of the IP address works correctly, but a profile checkname fails to resolve the IP address, then the RPC Binding Order may be incorrect. Ensure the RPC Binding Order includes ncacn_ip_tcp first in the list. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
   136516  (http://support.microsoft.com/kb/136516/ ) Improving Windows client startup times

IP Address Resolves?

If the IP address quickly resolves to the correct Microsoft Exchange Server name, continue with Host Name Resolution Troubleshooting below:

Host Name Resolution Troubleshooting - Ping Microsoft Exchange Server Name

At this point, the computer running Microsoft Exchange Server is available for connection via IP address. The next step is to verify host name resolution. At an MS-DOS prompt, ping the Microsoft Exchange Server name.

Ping Server Name Succeeds?

If pinging the Exchange Server Name works in a timely manner, but client starts up slowly, the RPC binding order may need to be modified. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

Ping Server Name Fails?

Run ipconfig /all (or winipcfg on Windows 95) and check what address is set in the Domain Name Server (DNS) entry field. DNS can be set for all TCP clients by means of Dynamic Host Configuration Protocol (DHCP) or by using the TCP Configuration in Control Panel for the individual computers. Continue with DNS Configuration Troubleshooting below.

DNS Configuration Troubleshooting - Ping DNS IP Address

If ipconfig displays an IP address in the DNS Servers field, then the client machine is configured to resolve Host Names via DNS. The next step in trouble shooting is to verify the DNS Server is available. At an MS-DOS prompt, ping the DNS IP Address. If the DNS does not respond to the request, additional attempts are made at 5, 10, 15, 20, 5, 10, 15, and 20- second intervals. This is the design of DNS and is usually the root cause of slow client startup.

Ping DNS Server Fails?

If the client computer is configured for a DNS server that is not available, DNS either needs to be disabled or needs to be configured for a DNS server that is available at all times.

If there are name resolution problems on the network some of the messages an Exchange or Outlook user may receive are as follows: -or-

Ping DNS Server Succeeds?

If the DNS server is available and configured properly, the Microsoft Exchange Server name and IP address need to be added to the DNS database. After this is done, pinging the Microsoft Exchange Server name will resolve to an IP address by the DNS server, allowing for faster startup times of the Microsoft Exchange client.

Add Microsoft Exchange Server to HOSTS File

The HOSTS file gets read every time a Winsock application attempts to resolve a host name. There are NO #PRE options to preload entries (that is how it is done in LMHOSTS). You can add the Microsoft Exchange Server entry to the HOSTS file and try again without having to restart Windows. The HOSTS file for Windows 95 is located in the Windows directory, and the HOSTS file for Windows NT is located in the %systemroot%\system32\drivers\etc\ folder.

Name Resolution

Below is the order of host name resolution over TCP/IP:

1. HOSTS fileDNS ServerNetBIOS CacheWINS serverBroadcastLMHOSTS file
2. DNS ServerNetBIOS CacheWINS serverBroadcastLMHOSTS file
3. NetBIOS CacheWINS serverBroadcastLMHOSTS file
4. WINS serverBroadcastLMHOSTS file
5. BroadcastLMHOSTS file
6. LMHOSTS file