Fatal error in joomla site?

after uploading a file in joomla site this error come

Fatal error: Cannot call overloaded function for non-object in /webcorp1/www/corpusers/p/u/punjabtourism.gov.in/libraries/joomla/utilities/simplexml.php on line 607

Fatal error: Class 'JLoader' not found in /webcorp1/www/corpusers/p/u/punjabtourism.gov.in/libr开发者_Python百科aries/loader.php on line 161

anybody have solution please help

Disable caching and see if that helps the problem - or, if you're using APC caching, then switch to just simple file caching.