A :You can have different root directories for different groups of users , all "Automatically"

for example , the following lines are the content of your virtual file system file (*.vfs)

C:\FTP-root\%g|/|me|admin|744|r|0|0|0|0|0|0|0|0|
C:\FTP-files\music|/music|me|root|744|r|0|0|0|0|0|0|0|0|
C:\FTP-files\video|/video|me|root|744|r|0|0|0|0|0|0|0|0|
C:\FTP-files\school|/school|me|root|744|r|0|0|0|0|0|0|0|0|

Then on your file structure should look like this:

C:\
|
+\FTP-root
| |
| +\group1
| | |
| | +\music (empty)
| | +\video (empty)
| +\group2
| | |
| | +\music (empty)
| | +\video (empty)
| | +\school (empty)
| +\Any other groups
|
+\music (files here)
+\video (files here)
+\school (files here)

Whatever blank directories exist in the groups ROOT directory (C:\FTP-Root\group) are the what a client will see. All others will be invisible.

It doesn't matter what your owner and group are set to in order to get the listing to work this way.

so if an user from group1 logins to the FTP server , he only sees music/video directories , and when an user from group2 logins your FTP server , he can access all 3 dirs music/video/school