In MOSS 2007, you can perform either a full or an incremental crawl. In most environments, an administrator will schedule the crawls so they take place automatically. However, in certain situations, you may need to perform a manual crawl (for example, if you apply a crawl rule to the content).

Keep in mind that a full crawl is more taxing on CPU and memory than an incremental crawl. Another thing to note is that once you start a crawl, you may not want to stop it. In other words, it may be advisable to let the system finish the crawl -- or if you must, simply pause it.

On that note, a word of caution: You should consider the pros and cons of stopping versus pausing a crawl. When you stop a crawl of a content source, MOSS 2007 automatically performs a full crawl the next time you crawl that content source. This is true even in situations where you perform an incremental crawl and then stop it. For this reason, depending on your situation, it might be best to consider pausing the crawl rather than stopping it.

To manually start a full or incremental crawl, start SharePoint 3.0 Central Administration console. Then, follow these steps:

1. In the Quick Launch area, under Shared Services Administration, click on a shared service.
   
   
2. On the Shared Services Administration, page click Search administration in the Search section.
   
   
3. On the Search Administration page, in the Quick Launch area, Click Content sources in the Crawling section. You may not see Search administration listed in that section if you don't have the Infrastructure Update for Microsoft Office Servers installed. In that case, click Search settings in the Search section in Step 2, then perform Step 3.
   
   
4. On the Configure Search Settings page, click Content sources and crawl schedules, which is the first link on that page in the Crawl Settings section.
   
   
5. On the Manage Content Sources page, move your mouse cursor over the content source that you want to crawl.
   
   
6. Click on the drop-down arrow next to the content source and then click either Start Full Crawl or click Start Incremental Crawl.