Thread:Project:Support desk/Vector Skin Not Loading After Update to 1.22/reply

What does "stopped working" look like for you? If all you see is a blank page, then follow the instructions on blank page and give us the error message! Checking the PHP error log might be a good idea anyway - it often contains useful information!

I guess that you have some kind of caching problem; try to empty all caches you can think of (MediaWiki, Apache, PHP code cache, proxy cache, browser cache...) and try, if it solves the problem.