OCS 2007 Automatic Sign-In Troubleshooting Tool
Here is great tool to help diagnose Office Communicator 2007 sign-in issues.
It runs on the client machine and specifically queries the following DNS records and displays the results.
- _sipinternaltls._tcp.<domain.com>
- _sipinternal._tcp.<domain.com>
- _sip._tls.<domain.com>
- _sip._tcp.<domain.com>
- sipinternal.<domain.com>
- sip.<domain.com>
- sipexternal.<domain.com>