virtualbox.org

Windows longhorn build: 5048

I already activated the partition using the cmd commands as usual, but after I did that and select the partiton I get this message saying:

The selected partition is not large enough to hold a Windows installation. Please extend the selected partition or select a larger partition

I know I have to extend it, but the most I can extend it to is at 1128 MB which is below the recommended size

I've searched on the internet a lot but I can't find any solution to this

Only the fact that you are posting in the Virtualbox forum shows me there's anything related to Virtualbox in your issue.

Are you actually trying to install Longhorn in a Virtualbox guest? If so, please see Minimum Info Needed for Assistance

Resize the drive, then the partition.

How to resize a Virtual Drive.