Extend Windows Partition Size - Fix `Extend Disk` greyed out

 

open cmd and run "diskpart"

# List the hard disk 
list disk 

# Select the hard disk 
select disk 0 

# list the partitions 
list partition

# Select the partition that you want to delete and allocate it to new partition
# if you are allocating it on a VM, just create a new partition, assign a volume to it 
# then delete it 
select partition 4

#Delete the partition 
delete partition override

now go to `Disk Management` --> right click on the partition that you want to extend
#you should observe Extend disk is not grayed out 
Select "Extend Disk" and now you can increase the Partition size