Thread:Project:Support desk/Fatal exception of type MWException after upgrade to OSX server yosemite

I use MediaWiki 1.23.0 with OS X server mavericks. However after upgrade to OS X 4.0 yosemite, It shows error '[43887455] 2014-10-21 00:38:56: Fatal exception of type MWException' with the title of Internal error. I have no idea of how to solve. Anyone can advice me? Please let me know the solution.