Where are your data files?
I am guessing that you installed the default settings?
In which case your data files are stored under the user folder/profile created for the user id who installed them on your computer. They cannot then be accessed by other users.
The VGHD data & models folders are not in the same location as the program files. The default locations are:
program - C:\Program Files\VGHD
Data - C:\Documents and Settings\profileName\VGHD\Data
Models - C:\Documents and Settings\profileName\VGHD\Models
VGHD was not intended to be used across multiple accounts, however here is a topic that discusses this issue and has some suggestions:
http://www74.virtuagirlhd.com/us/forum_post.php?foId=4&ftId=8050