I installed VirtualBox 4.3.28 in Windows 8.1 and am running CentOS 7 within it. But the problem is that VirtualBox is placing a size limit on the frame within which CentOS 7 is visible. Here is a screenshot:

enter image description here

As you can see, I maximized VirtualBox, but there is a lot of white space surrounding the CentOS 7 window. I need to open lots of documents with small text in CentOS.

How can I get rid of the white space so that CentOS 7 fills the entire space available in VirtualBox 4.3.28?

  • Install virtualbox guest utils (search for it) and that should fix it. I know this has been asked somewhere else on stack exchange; a quick search should give you your fix. Link is here: forums.virtualbox.org/viewtopic.php?f=3&t=15679
    – Abraxas
    Jun 20, 2015 at 0:05

1 Answer 1


From the top...

Become the root user with su - or sudo -i. Install software needed to compile the kernel module.

yum install -y kernel-devel gcc make

or (with more than you need but also a good method):

yum groupinstall -y 'Development Tools'

Update all software mostly to make sure that the kernel and its sources match:

yum update

With CentOS 7 running, choose Devices -> Insert Guest Additions CD Image. Do not automatically run the script on the virtual optical device. Become the root user with su - or sudo -i. And then mount the virtual optical device somewhere normal:

umount /dev/sr0
mount /dev/sr0 /mnt

Run the installer:


There may be a superfluous reboot in here somewhere depending on the state of your software, but now you can enjoy the features of VirtualBox Extensions!

  • That did it! Thank you and +1. In my machine, the Devices -> Insert Guest Additions CD Image step led to automatically running the VBoxLinuxAdditons... through the GUI. And also, a preceding reboot got hung up for over half an hour so I had to just manually pull the power switch and reboot, breaking the update process. But otherwise, your methods guided the solution and it works now. No more shrunken image. CentOS fills the screen. Thank you.
    – CodeMed
    Jun 22, 2015 at 21:19

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .