The Google Desktop Search software became officially defunct toward the end of 2011. But one can still download the last 5.9.1 version, and it happily installs and indexes and searches the full-text of your content. For instance, a folder full of Gbs of PDF encyclopaedias and journal articles, ebooks, etc, presenting results in a familiar Google Search interface. Note the indexing has to be manually started by you, and this is done by right-clicking the taskbar icon and selecting “reindex”…

But if you need a personal desktop search product that’s being supported and developed, perhaps due to the need to index a new file-format, then the alternatives are…

* the free ad-supported Copernic Desktop Search. Well-reviewed and mature software. Can be a bit aggressive in its initial indexing, but then it works quickly and intuitively. There is also a Copernic Desktop Search Professional Edition. The best everyday replacement for Google Desktop Search.

* dtSearch Desktop (£119, PC World review from 2011). A very mature and powerful software, although the price of $199 will likely make it unappealing to personal users. The dauntingly powerful interface will also likely make it unappealing to small business users.

* the new X1 Desktop Search. The X1 website’s main landing page seems to be positioning the X1 range for the corporate market.

* DocFetcher 1.1 is a Java-based desktop search software, that’s open source and free. It’s been around since 2009, but doesn’t seem to have any genuine reviews (that I could find). Supports indexing of Open Office file types.

* the free built-in Windows 7 search. Although now tamed, and no longer the fearsome disk-grinding Windows Vista incarnation, in my view turning on Windows Search still makes a desktop PC too slow. Especially if you run a PC stuffed to the top with legacy files and emails.

SearchMyFiles (freeware)

Effective File Search (freeware)