Problem Description: no items indexed anymore during the crawling process
From one day on the other, no items got indexed anymore during the crawling process on our Microsoft Office SharePoint Server 2007 installation.
Looking in the Crawl logs, following error was found: Access is denied. Check that the Default Content Access Account has access to this content, or add a crawl rule to crawl this content. (The item was deleted because it was either not found or the crawler was denied access to it.)
Solution: registry modification
Nothing was changed to the Windows account used as default content access account. Pretty soon we realized that a Windows update had been executed recently on the SharePoint server. After this Windows update, the crawling process started to go in failure.
After having followed the instructions of the Knowlege Base article, the SharePoint crawling process went again smoothly as before.