So, you upgraded from Windows 7 or 8.1 to Windows 10. Good move. But out of the blue something weird happens. Maybe the Desktop does not look normal, the Task Bar is missing, the Start button does not work properly, etc. What to do? Well, assuming that your system is free of malware, if a restart does not correct the glitch, there are three common procedures to try first that may help diagnose the problem:
1. Boot in Safe Mode (which may help isolate the problem to 3rd party add-ons).
2. Try logging into another user account (which may help isolate the problem to corruption of your account).
3. Try restoring to a recent Restore Point before the problem arose (which may revert the system to a healthy state).
These procedures require access to the Control Panel or System Configuration; so, if that’s not possible in the usual ways, then another method is required.
1. If you’ve not done so already, you may try booting into Safe Mode by following this PC World article, at this link:
http://www.pcworld.com/article/2984712/windows/how-to-enter-windows-10s-safe-mode.html
The first method they describe won’t help if the Start button does not work. So, further along they note that, “If you can get to the login screen, you’ll find a power icon in the lower-right corner. The instructions above work there.”
The last method requires a Windows 10 Recovery Drive, which the article discusses how to create. If you can get to the Control Panel, you might try that.
Here’s another article on Safe Mode:
http://www.digitalcitizen.life/4-ways-boot-safe-mode-windows-10
If you can get to the Run dialog box, then you can invoke “msconfig” and follow the instructions.
Enter Windows Key + R (the plus sign is NOT typed — it indicates that you need to hold down the Windows Key [Windows logo key] and then type another key) to get the Run dialog and then enter “msconfig” in the box after the “Open:” label.
2. Although some of the articles I found do not mention it, you can create another user account via the Control Panel, which allows you to get at the Settings windows to actually do so.
On the Control Panel > All Control Panel Items, click on User Accounts, then Manage Another Account, then on “Add a new user in PC settings.” Then follow the instructions (reference article below as well).
3. You can check if System Protection is enabled from the Control Panel > System and clicking on (in left side) “System protection.” Protection should be “On” for your “C” (boot) drive. So, if that’s enabled, you can check Restore Points by clicking on the “System Restore” button. If you have some restore points, you may try that procedure. (You know how to create your own Restore Points, correct?)
Finally, how can you get to the Control Panel if the Start button is not working or any of the usual ways? Enter Windows Key + R to get the Run dialog and then type “control panel” and click the “OK” button.
References:
Microsoft’s official page on Safe Mode:
http://windows.microsoft.com/en-us/windows-10/start-your-pc-in-safe-mode
Microsoft’s official way to create another user:
http://windows.microsoft.com/en-us/windows-10/create-a-local-user-account-in-windows-10
Microsoft’s official page on system recovery:
http://windows.microsoft.com/en-us/windows-10/windows-10-recovery-options
So, coincidentally, PC World released some how-to videos recently.
How to enter Windows 10 Safe Mode:
http://www.pcworld.com/video/61624/how-to-enter-windows-10-safe-mode
How to make a Windows 10 Recovery Drive:
http://www.pcworld.com/video/61703/how-to-make-a-windows-10-recovery-drive