7. Metro apps don't work anymore
On a lot of users' systems, Windows 8 apps refuse to launch or just freeze shortly after displaying the startup splash screen
Solution: This is a known bug in Windows 8 that is tied to the user account control (UAC) feature. If it's turned off (either by the user or some third party application), some apps might not work properly. To re-enable UAC, go to the Start screen, search for "User Account Control" and click on "Settings". Click on "Change User Account Control Settings" and move the slider to the default setting. Also, make sure not to use the built in Administrator account to run Metro style apps -- use your own user account instead.
8. Windows 8 requires a product key
The Windows Developer Preview is a public pre-beta and shouldn't require a product key. Yet, some users were prompted with a "Please enter product key to proceed" window either when installing Windows, when running Windows 8 off of a USB key ("Windows To Go") or after they repaired the OS using the Windows Refresh feature.
Solution: To get rid of the product key check, Microsoft advises users to re-download the ISO from the MSDN website and install everything all over. However, that might not be the perfect option if you've already spent hours downloading, installing and configuring your Windows 8 test PC. A quicker method is to use a key provided by Microsoft's Support that works universally across all Windows 8 Developer Preview builds. Simply type in:
6RH4V-HNTWC-JQKG8-RFR3R-36498 (for the Windows 8 Client) 4Y8N3-H7MMW-C76VJ-YD3XV-MBDKV (for the Windows Server 8)
That should be it to activate your Windows 8 Dev Preview!
9. .NET Framework 3.5 is missing
By some weird happenstance, Microsoft decided to omit the .NET Framework 3.5 from its Windows 8 Developer Preview, which has version 4.0 running only. If you're trying to install an application that requires 3.5, you'll be faced with a dialog saying it needs to download the required components. Unfortunately, this process either takes half an eternity (45 minutes on some of my machines!) or results in error messages.
Solution: Gladly, there's a way to run the offline installer on the Windows 8 Developer DVD. Just make sure that the DVD is in the drive (or the ISO is properly mounted), fire up a command prompt and type in:
dism.exe /online /enable-feature /featurename:NetFX3 /Source:x:\sources\sxs
Note: X is the letter of your DVD or ISO drive. This should launch the installer immediately.
10. Programs and drivers won't run
I think it's nothing short of a miracle that nearly all of my Windows 7 applications and drivers work right out of the gate. Microsoft's legacy support is spot on, even in this early pre-beta release of Windows 8. However, there is a small portion of programs and drivers that just won't work, due to the fact that Windows 8's version number jumped from 6.1 (Windows 7) to 6.2 and some installers' version checks simply refuse to run.
Solution: I won't bore with the various compatibility modes (as you probably tried that already), but rather point you to part 3 of my "Running Windows on a Mac" series in which I describe some steps to get rid of version checks. More precisely, it details how to remove the Windows version check of an installer file using "Orca MSI Editor" or remove the version information from "*.inf" driver files. Of course, these steps work differently on all drivers and installer files, but it'll give you the basic idea of how to force your "legacy" software to run on Windows 8 Developer Preview and later.
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