i`m unable to login my guest user a/c
 i don`t know what the problem is about but whenever i`m clicking the guest user icon in the windows login page -
 it says - Group policy client service failed to logon
               Access is denied.
 
  anybody please help!There is some confusion about guest account in Windows 7 as explained by Microsoft support.  Please read this carefully
http://windows.microsoft.com/en-us/windows7/Turn-the-guest-account-on-or-off
If you still have problems, come back here and there are volunteers here that will give you more help.the link `s of no use
guest account in inaccessible, though i can disable it Quote

1. make sure your NIC driver does not have Microsoft’s driver as this CAUSES many problems, download and install the latest driver from manufacturer

2. if you are using Symantec antivirus 10.2 then upgrade it to Symantec11 endpoint protection, or download and install the latest client if you using any other antivirus software

3. make sure your network switches are configured correctly, if you are not sure, then bring in a pro to have a look

4. make sure you got all the patched and service packs on your build

Ok this worked for me. Log on using a DIFERENT account. run REGEDIT (this edits the registry). Go to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList there is a list of sids here. These security IDs are what links the useraccount to the profile. Each user account has a sid.  Click on the sids and you will see a ProfileImagePath key in the right hand key. Use this to figure out the effected profile. It will say something like %SystemDrive%\Users\username write this down you will need it later. Once you know which user account the sid is for.Delete the Sid from the profile list hive (just right click on it and hit delete). Now restart and log on as the user you couldn't log in as. It will create a new profile all your settings will be gone. Log off and log back on as a local admin. Go back to regedit and navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList again. This was repopulated when you logged back on. Now SELECT profile image path and set it back to what it was originally. See if you can log back in as the user.