After Installing linux ubuntu on Oracle VM virtual box, the next big problem I faced was the blank screen after entering password on Login. Since the command line was properly working and the login screen too was displayed properly, I was sure there isn't any problem with the installation process. I Googled it and Ubuntu forum was flooded with the same question.
I found an appropriate answer to the question in one of the thread and got my problem fixed. The blank screen after entering password on Login was due to the fact that "Virtualization was disabled by default in my Windows 7". All I had to do is to enable the virtualisation. The same case might be with you.
Enable Virtualisation Technology.
I used to get a blank screen without any cursor and options/menu.
It was frustrating. If the same case is with you, you can overcome the blank screen of Ubuntu in VM virtual box by enabling your CPU Virtualisation in the BIOS setting.
Follow these steps.
Step 1: Restart your System and press "Escape" key on the start up to enter the Start Up Menu. (The key may vary depending on your system manufacturer).
Step 2: To enter BIOS Setup, press F10.
Step 3: Navigate to the System Configuration in BIOS setup menu.
Step 4: You will find the "Virtualization Technology" disabled by default. Enable it, save and exit.
Note: I am using HP Pavilion dv6 Notebook PC with 6GB RAM. The keys may be different for your make and model. Read your manual or search over web about it.
Now, you have done the work. All you have to do is restart your VM Ware and Login to Ubuntu with the username and password. The Blank Screen that appeared earlier after logging in has now been replaced with the Ubuntu Desktop.
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