Help me error webmail

[myonline]

when i connect to webmail.mydomain.com i recieved report error
Fatal error: Call to undefined method: registry->setlanguageenvironment() in C:\inetpub\vhosts\webmail\horde\lib\Horde\Registry.php on line 824

I don't know why?

I hope everyone help me for that

thanks


Phan