can not create new domains

[Ayad Mohamed]

Hi

I have a problem in plesk 9.0.1 installed on linux redhat enterprise 5 ,
whenever I tried to create a domain I get the following error ,

Unable to get hardquota state: usermng failed: usermng: get_device: Cannot chdir to /var/www/vhosts

System error 2: No such file or directory

0: /usr/local/psa/admin/plib/class.PHostingManager.php:248
PHostingManager->initFromTemplate(object of type Template)
1: /usr/local/psa/admin/plib/ui/client.domain.hosting.setup.php:219
plesk__client__domain__hosting__setup->accessItem(string 'POST', NULL null)
2: /usr/local/psa/admin/plib/UIPointer.php:596
UIPointer->access(string 'POST')
3: /usr/local/psa/admin/htdocs/plesk.php:36

Can anybody helps please ?

Regards
Ayad