Generally, when your laptop has viruses, or system errors, or is slow due to a software update, you would be asked to do a factory reset so that your laptop can start functioning normally. You would have to back-up any personal files or data to save.
So for your HP Envy laptop having Windows 8 Operating System, then follow these steps carefully to do a factory reset.
Go to search and type in Recovery.
You would get HP Recovery Manager, which you have to choose. You would now get a menu having three columns.
Then go to the option I need immediate help found on the left of the menu. Choose the option Windows Recovery Environment and confirm to reboot your laptop for the system recovery to start.
Now, your laptop would restart and you would get a menu called Choose an option.
Now, you would have to select Troubleshoot and then in the next menu go for Recovery Manager.
Then again in the Recovery Manager select the option Microsoft System Restore under the column I need immediate help. Then you would have to approve for system restore.
Now, the laptop would be taken to factory settings.