I finally solved the issue with steps I found in some page, I couldn't paste the link here because this forum doesn't allow newbies with less than 10 posts to post links.. so I'll just paste the steps here.
1.Open Windows PowerShell as Administrator
Method 1:
a.Press Windows Key + R on your keyboard
b.Key in PowerShell and hit Enter.
c.Right click on the PowerShell icon on the taskbar and select Run as Administrator.
Method 2:
a.Right click Start button
b.Choose Command prompt (Admin)
c.Key in Powershell in the black window and hit Enter.
2.Paste the following command in the Administrator: Windows PowerShell window and press Enter key:
Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml"}
3.Wait for PowerShell to execute and complete the command. Ignore the few errors (in red color) that may pop up.
4.When it finishes, try hitting Start and hopefully it’ll start working. If not, this solution won’t apply to you, unfortunately.
source : wwwDOTtechmestoDOTcom