Certificate security warning for a SharePoint site when you start Outlook


Symptoms


When you configure Microsoft Outlook to have one or more Microsoft SharePoint calendars or lists, and then you start Outlook, you receive the following certificate security warning:
The name on the security certificate is invalid or does not match the name of the site.

Cause


This issue occurs because of the Alternate Access Mappings setting on the SharePoint server. When SharePoint servers are on the same network as Outlook, the Intranet Zone mapping in SharePoint takes precedence over the Default mapping. If the intranet URL does not match the certificate URL, you receive the security alert that described in the "Symptoms" section.

Resolution


To resolve this issue, use either of the following methods.

Method 1

To manage alternate access mappings on the SharePoint server, follow these steps.
  1. Click Start, click All Programs, click Microsoft Office Server, and then click SharePoint 3.0 Central Administration.
  2. On the Central Administration home page, on the top navigation bar, click Operations.
  3. On the Operations page, in the Global Configuration section, click Alternate access mappings.
  4. Click the URL that is listed as Intranet.
  5. Update the URL to match the URL that is listed on the certificate. Or, click Delete to remove the entry.
  6. Click OK to save changes.

Method 2

Use a certificate that matches the URL in the Intranet zone list on the SharePoint server.