1.
Press Windows logo key + R,
type ms-settings:, and then select OK. This opens
Settings.
2.
In Settings, choose Update & security > Windows Update ,
and then select Check for updates. Install any available updates
and restart your PC if required.
If you didn’t have any updates that required a restart, it’s still
a good idea to restart your device to make sure any pending updates are
installed.
For assisted support, try the Start menu troubleshooter.
After you've completed the troubleshooter, restart your device.
If you still can’t open the Start menu or Cortana, try creating a
new local administrator account to see whether you can open the Start menu
using that account.
If you're signed in with your Microsoft account, remove the link
to that account first by doing the following (otherwise see "Create
the new administrator account"):
1.
Press Windows logo key Windows logo key + R,
type ms-settings:, and then select OK. This opens
Settings.
2.
Select Accounts > Sign in with a
local account instead.
3.
Type your Microsoft account password and select Next.
4.
Choose a new account name, password, and password hint, and then
select Finish and sign out.
Create the new administrator account:
1.
Press Windows logo key + R,
type ms-settings:, and then select OK.
2.
Select Accounts > Family &
other people (or Other people , if you’re using
Windows 10 Enterprise).
3.
Under Other people , select Add someone
else to this PC.
4.
On Windows 10 Home and Windows 10 Professional, provide a name for
the user and a password, and then select Next. On Windows 10
Enterprise, select I don’t have this person’s sign-in information,
and then select Add a user without a Microsoft account.
5.
Set a user name, password, and password hint. Then select Next > Finish.
Next, make the new account an administrator account.
1.
Under Family & other people (or Other
people , if you're using Windows 10 Enterprise), choose the account
you created, and then select Change account type.
2.
Under Account type, select Administrator > OK.
Sign out of your account and then sign in to your new account. If you can open Cortana or the Start menu, move your personal data and files to the new account.
If the problem still isn't fixed, try deleting the old
administrator account:
1.
Under Other users, select the old administrator
account, then Remove > Delete account and data.
2.
After the old account is removed, restart your device and sign in
with the new account again.
If you were using a Microsoft account to sign in before, associate
the Microsoft account with the new administrator account. In Settings > Accounts ,
select Sign in with a Microsoft account insteadand enter your
account info.
If none of the previous options work, try resetting your PC using Windows 10
recovery options.