SharePoint Server Search Service is filling up your C:\ drive by writing its search index to C:\Program Files\Microsoft Office Servers\12.0\Data\Office Server\Applications.
When you configure SharePoint one of the first services started is the SharePoint Server Search Service(MOSS 2007). It’s a common mistake to allow your shared service provider to utilize the default search index location: C:\Program Files\Microsoft Office Servers\12.0\Data\Office Server\Applications . As your search corpus grows, so does the search index (at roughly 30% of the corpus) eventually the resulting index files will overload your operating system’s drive.
Log into central administration and select “Services on Server”
Select “Office SharePoint Server Search”
Note the index location
Using stsadm (located at C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\BIN) run the following command
Stsadm -o osearch -defaultindexlocation “e:\search index”
