1. Would not recommend using a PERIOD in the user's folder name either.
2. Would not create all the shares off the root of a volume or drive. Better to have something like D:\USERS and then create all user folders and shares under D:\USERS
3. Would also use USERID as the name of the folders

Here is some example code that assumes the @FullName is setup with FIRST -space- LAST There is no error checking or validation either which might be required if there is a typo in the user's @FullName description.

Break On
$Server = 'SERVER01'
? 'Full: ' + @FullName  ; Assumes [John Smith] 
? 'UserID: ' + @UserID  ; Doesn't matter - code uses only @FullName 
? 'Home Folder: ' '\\' + $Server + '\' + Left(@FullName, 1)+'.'+Split(@FullName,'')[1]+'$'
 

; Gives you \\SERVER01\J.Smith$