Has it ever happened to you that old cached URLs keep lingering around and causing problems in your TYPO3 installation boosted up with realurl? I know it happened to me plenty of times. The usual way to handle the discrepancy between realurl cached URLs and the reality is to visit the Info module and it's corresponding 'Speaking Url Management' dropdown item. This would then allow you to visit each of the: ID-to-path mapping, Decode cache, Encode cache and Unique Aliases in order to fully clear the realurl cache and cause the rendering of updated speaking urls.
There is a much better and a lot more convenient way to this though. That way is called realurl_clearcache. It will add a single item to the cache dropbox in the upper right corner of your screen (TYPO3 4.3, the lightning icon in the upper right corner), namely the 'Clear RealURL Cache'. This action will allow you to do in a single click the entire work of clearing: ID-to-path mapping, Decode cache, Encode cache and Unique Aliases. Very useful indeed and from now on in my collection of default extensions.
Seems like a good idea to refill the RealURL Cache immediately after it has been cleared. It appears that this can be easily done. Dmitry Dulepov, the author of RealURL extension proposes this simple solution:
From time to time I see this question: how to fill RealURL cache with page addresses?
The answer is pretty simple. Make a new "hide in menu" page. Insert Sitemap there. Logout from Backend. Enter that new page address in the browser bar.
Notice that logging out is essential. RealURL will not cache anything if you are logged in to Backend.
This procedure will fill cache with page addresses. But it will not create cached entries for stuff like tt_news. So this tip is good if you have mostly pages.
- taken from How to fill RealURL cache by Dmitry Dulepov.