Make sure virtualisation is enabled in the BIOS.
Also if you have AVAST or AVG antivirus then the following might be relevant.
Are you running AVG, Avast or BitDefender 2017 antivirus at the host OS?
If AVG or Avast then see:
for a solution on using both antivirus products along with VMware
In Avast Settings, troubleshooting you should uncheck the "Enable hardware-assisted virtualization" feature.
In AVG Settings, troubleshooting, uncheck "Enable hardware-assisted virtualization" feature.
Note that you will have to reboot to apply the change.
If you are running BitDefender 2017 at the host then the only solution that I am aware about is to uninstall and revert to an older version of BitDefender.
Wil| Author of Vimalin. The virtual machine Backup app for VMware Desktop Products
| Vimalin : Automated backups for VMware Fusion and VMware Workstation Professional
| More info at https://www.vimalin.com
| Twitter @wilva
| VMware Wiki at http://www.vi-toolkit.com