FHC has been test and works correctly with both Microsoft Vista and Windows 7, however depending on your security settings you may get some unwanted error messages.  The messages are as a result of the security model of the operation system.  The following will proved a solution to most issues:  

Find the FHC icon on your desktop and then select ‘Properties' the select the ‘Compatibility' tab.  You should see at the bottom a label ‘Privilege Level' and a check box ‘Run this program as an Administrator' please ensure this check box is selected.   
 
You may also wish to tune off the ‘User Account Control' but before doing so please satisfy yourself of the security risk.  You will find more information about UAC at:

http://support.microsoft.com/kb/922708
http://www.howtogeek.com/howto/windows-vista/disable-user-account-control-uac-the-easy-way-on-windows-vista/