SP2007 - Web Part Error: One of the properties of the Web Part has an incorrect format.

Web Part Error: One of the properties of the Web Part has an incorrect format. Windows SharePoint Services cannot deserialize the Web Part. Check the format of the properties and try again.

Windows directory
%WinDir%\Temp
Administrators - Full Control
SYSTEM - Full Control
WSS_WPG - Read, Write
Network Service (for a domain controller only) - Read, Write

%WinDir%\system32\logfiles
STS Administrators - Full Control
SYSTEM - Full Control
WSS_WPG - Read, Write
Network Service (for a domain controller only) - Read, Write