Black screen display on VM

Black screen display after login virtual machine. Don’t know why?
I have increased video memory from 16MB to 64MB but still, it didn’t work. Repeated more time to power off and turn on a virtual machine but still, it didn’t work.

@VenkataRamanen Could you please elaborate on your issue? Were you able to access Ubuntu Desktop earlier or is this the first time? On which step are you getting Black screen like this ?

After login with password, the blank screen appears in virtual machine. Even I did uninstall both VIRTUAL BOX and UBUNTU OS. After did fresh installation, it works fine. But after some time, same problem continues. Don’t know why?

@VenkataRamanen Could you please try the solution mentioned in