Windows RT 8.1: FAQ
Update to Windows 8.1 from Windows 8
Why can't I find the update in the Store?
Why can't I activate Windows?
Get help with activation errors
What is a product key?
Get answers to your questions in the Windows forum.
Get help from a support professional by phone, email, or chat.
What's new in Windows 8.1 Update and Windows RT 8.1 Update?
Update to Windows 8.1: FAQ
Upgrade Assistant: FAQ
Upgrade to Windows 8.1 from Windows 7
Upgrade to Windows 8.1 from Windows Vista or Windows XP
Add features: FAQ
How to perform a clean installation of Windows
Upgrading with a metered Internet connection
Retrieve files from the Windows.old folder
What to do if Windows 8.1 Setup stops responding
What are the Windows 7 system requirements?
32-bit and 64-bit Windows: frequently asked questions
Is my PC running the 32-bit or 64-bit version of Windows?
Installing and reinstalling Windows 7
Windows installation problems: frequently asked questions
Install more than one operating system (multiboot)
Install Windows 7 Service Pack 1
What's included in Windows 7 Service Pack 1 (SP1)
Troubleshoot problems installing Windows 7 Service Pack 1
Upgrading from Windows Vista to Windows 7
Upgrading from Windows XP to Windows 7
Which version of the Windows operating system am I running?
Upgrade to another edition of Windows 7 by using Windows Anytime Upgrade
Invalid Windows product key
Activation error 0xC004F061
How do I activate Windows?
Activating Windows: frequently asked questions
Get answers to your questions in the Windows 7 forum.
Installing and reinstalling Windows Vista
Learn how to install Windows Vista Service Pack 2 (SP2)
What's included in Windows Vista Service Pack 2 (SP2)
Troubleshoot Windows installation problems
Upgrading from Windows XP to Windows Vista
Upgrade to another edition of Windows Vista
Troubleshoot activation problems
Where do I find my Windows product key?
Get answers to your questions in the Windows Vista forum.
As of April 8, 2014, support and updates for Windows XP are no longer available. Find out how to stay protected.
Set up Windows XP for multiple input languages
Get answers to your questions in the Windows XP forum.