Compatibility issues tend to occur with the following technologies:
- User Account Control (UAC): Adds
security to Windows by limiting administrator-level access to the
computer, restricting most users to running as Standard Users. UAC
limits the context in which a process executes to minimize the
ability of the user to inadvertently expose the computer to viruses
or other malware. UAC affects any application installer or update
that requires Administrator permissions to run, performs
Administrator checks or actions, or attempts to write to a
non-virtualized registry location.
- Windows Resource Protection (WRP):
Enables applications to function properly even if an application
attempts to write to protected system files or registry locations.
WRP creates a temporary work area and redirects write actions for
the application session. WRP affects any application installation
that attempts to replace, modify, or delete protected operating
system files or registry keys. Attempts typically fail and return
an Access Denied error.
- Internet Explorer Protected Mode:
Helps to defend against elevation-of-privilege attacks by
restricting the ability to write to any local-computer-zone
resources other than temporary Internet files. This mode affects
any website or web application that attempts to modify user files
or registry keys or that attempts to open a new window in another
- Deprecation: Any application that uses
.dll files, executable (.exe) files, COM objects, registry keys,
APIs, or other files that have been deprecated from previous
versions of Windows may lose functionality or fail to start.
- Graphical Identification and
Authentication (GINA) DLL: Prior to the release of
Windows Vista, independent software vendors (ISVs) were able
to modify authentication by installing a GINA DLL. The GINA DLL
performed the user identification and authentication.
The current authentication model does not require the GINA DLL and ignores all previous GINA DLLs. This change affects any application or hardware component that attempts to log on by using customized logon applications, including biometric devices (fingerprint readers), customized user interfaces, and virtual private network (VPN) solutions for remote users with customized logon user interfaces.
- Session 0: Prior to the release of
Windows Vista, the first user who logged on to a computer ran
in Session 0, which is the same session that is used for
system services. The current model requires all users to run in
Session 1 or later so that no user runs in the same session as
the system services. Applications will fail to start if they depend
on interactive services. An interactive service is any
service that attempts to send a window message, attempts to locate
a window or additional service, or attempts to run any user
processes that open the same named object, unless it is a globally
- Windows Filtering Platform (WFP): WFP
is an API that enables developers to create code that interacts
with the filtering that occurs at several layers in the networking
stack and throughout the operating system. If you are using a
previous version of the WFP API in your environment, you might
experience failures when running network-scanning, antivirus, or
- Operating System Version Changes: The
operating system version number changes with each operating system
release. The GetVersion function returns the version number
when queried by an application. This change affects any application
or application installer that specifically checks for the operating
system version and might prevent the installation from occurring or
the application from running.
- Windows 64-bit: 64-bit versions
of Windows use the Windows on Windows 64 (WOW64) emulator.
This emulator enables the 64-bit operating system to run 32-bit
applications. The use of this emulator might cause an application
or a component that uses 16-bit executables or installers, or
32-bit kernel drivers, to fail to start or to function