Windows 8.1, Server 2012 R2 App Compatibility Considerations

An application compatibility guide is available for Windows 8.1 and Windows Server 2012 R2. The guide could help developers identify compatibility problems with existing software on the new OS releases. Microsoft has also published a list of removed or deprecated features in Windows Server 2012 R2. Most applications written for recent Windows and Windows Server versions should work on the upcoming releases, but some might need updates to function properly. Existing applications should be tested for compatibility with the new OSs, which have been released to manufacturing, although updates will continue to arrive through the day that the OSs become generally available.

(Changes discussed here may affect software without user interfaces [such as services and drivers] and applications that use the Windows Desktop user interface, but applications that use the Windows 8 and Windows RT Modern user interface [such as Windows Store applications] may be impacted by other changes in Windows 8.1.)