Privacy workshop The Windows Indexing Service catalogues the contents of your hard disk, and even the contents of files, to make local searching faster.
This service creates and later consults a number of small databases containing data about your disk's contents, including the actual contents of files, which can undermine the practice of good data hygiene. Indexing creates what amounts to a scattered secondary volume of your data, and your wipe utility might fail to erase all these related traces when it erases a file.
However, the Indexing Service is also a significant convenience. It's not essential for searching, but it speeds up searches and enables you to search for strings within files. So it's not something to do away with unless you are primarily concerned about privacy and data hygiene.
There are two levels of response here, and you can choose your poison. First, indexing can be shut off altogether, and you can then wipe the index files and that will be the end of it. Second, you can shut it off temporarily, wipe the index files, and then re-enable the service, only this time selecting the particular directories to be indexed. This way, you can use the service, but prevent the indexing of directories containing sensitive information.
For those interested in the nuclear option, consider that, for an added bonus, disabling the Indexing Service will free up some processor resources and RAM. If you are unlikely to search very often, it's foolish to devote system resources to speeding up a service that you don't really depend on, or even want.
Of course, if you normally spend a great deal of time searching for files, or for strings of text within your files, you'll be grateful for the Indexing Service, although it does make data hygiene pretty much impossible if you index directories and files indiscriminately.
Regardless of which option you choose, begin by disabling the service and wiping the old index files. First, log in as an Administrator, and begin by shutting it off:
1. Go to the Start menu and choose Run.
2. Type in services.msc and click OK. The Services dialogue will launch.
3. Right-click on the Indexing Service to bring up the Properties dialogue, and click Stop if the service is running. Then select Disabled. Click Apply and close the dialogue.
4. Go to My Computer. Next, select (Local Disk C:) under "Hard Disk Drives".
5. Right-click on the (Local Disk C:) icon and choose Properties from the right-click menu. The Local Disk Properties dialogue will pop up. Near the bottom you will see a tick box beside the option: "Allow Indexing Service to index this disk for fast file searching" (the option will not be available on all systems, so don't worry if you don't see it).
6. Clear the tick box, click Apply, and in the next dialogue, select the option "Apply changes to C:\, subfolders and files." Click OK, and reboot.