Recently after I had configured a SharePoint farm I ran into this little error relating to the Search indexer. Found out this was related how the loopback adapter tries to resolve addresses when using Windows Authentication. The result is no matter how many times you try to crawl your SharePoint content sources (sites) you will get access denied for the Search content access account.

Detailed error message on the event log as follows.

Event Type: Warning
Event Source: Office Server Search
Event Category: Gatherer
Event ID: 2436
Date:  04/11/2008
Time:  10:32:31 a.m.
User:  N/A
Computer: WLGSPDSPOINT02
Description:
The start address <http://myporal> cannot be crawled.

Context: Application 'SSPKBPRD', Catalog 'Portal_Content'

Details: Access is denied. Check that the Default Content Access Account has access to this content, or add a crawl rule to crawl this content.   (0x80041205)

To fix this error follow these steps.

Specify host names for Search Indexer to work > http://support.microsoft.com/kb/896861

To specify the host names that are mapped to the loopback address and can connect to Web sites on your computer, follow these steps:

1. Click Start, click Run, type regedit, and then click OK.
2. In Registry Editor, locate and then click the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\MSV1_0
3. Right-click MSV1_0, point to New, and then click Multi-String Value.
4. Type BackConnectionHostNames, and then press ENTER.
5. Right-click BackConnectionHostNames, and then click Modify.
6. In the Value data box, type the host name or the host names for the sites that are on the local computer, and then click OK.
7. Quit Registry Editor, and then restart the IISAdmin service.