start you system in safe mode..
Press the Windows + R keys to open the Run dialog, type lusrmgr.msc and click/tap on OK. In the left pane, click/tap on the Users folder, then in the middle pane, Right click/tap on Administrator.
add/change password
restart in normal mode issue should be resolved.
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1.Press
Windows key + Q button to open Windows charms bar.
2.Type
‘cmd’ in the search and open it.
3.In Command Prompt type:
SHUTDOWN /R /O -T 00 and press Enter.
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4.Wait till the computer restarts and the advanced boot options are displayed.
5.Click on
Troubleshoot from ‘
Choose an option‘ screen.
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6.Next select
‘Advanced options.’
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7.Now in the advanced option menu, click on
‘Command Prompt.’
8.Command Prompt will open after the restart.
NOTE: You may need to enter administrator password or current user account password.
9.In cmd type
NET USER ADMINISTRATOR /ACTIVE:YES and press Enter to enable the
Administrator account.
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10.Now exit the command prompt by typing
exit and press enter.
11.From Choose an option window, click Troubleshoot then Advanced options and click
Startup settings.
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12.From the
Startup Settings window, click
Restart.
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13.Startup Settings window comes up again after the Windows restart,
press 4 on the keyboard to start in the
Safe Mode.
14.In Safe Mode click on the
Administrator account to log in.
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15.Once you are logged in Administrator account, you can
remove the old account and create a new one without errors.