What is the difference between Quick Format and Full Format?
Which option should you choose when formatting a drive?
When you choose to run a Full Format on a volume (or partition), files are removed from the volume that you are formatting and the hard disk is scanned for bad sectors. The scan for bad sectors is responsible for the majority of the time that it takes to format a volume.
When you choose to run a Quick Format on a volume (or partition), format removes files from the partition, but does not scan the disk for bad sectors. Only use this option if your hard disk has been previously formatted and you are sure that your hard disk is not damaged.
Windows Server 2012 (R2) Extend Volume Greyed Out issue
You are trying to extend partition with Disk Management snap-in Windows Server 2012 (R2), but you find the option to Extend Volume greyed out.
Reason 1: The cause is disk partition style. Your disk partition is MBR style that supports only up to 2TB.
Solution for reason 1: Convert MBR to GPT disk for using un-allocated space beyond 2TB.
Reason 2: The un-allocated space is not contiguously behind the target partition that you want to extend.
Solution 1 for reason 2: Step 1: Backup the partition (e.g. D:) behind the target drive (e.g. C:) you want to extend. Right-click on the D: partition and select "Delete Volume" in the drop down list. Step 2: Once you have D: partition delete, it will turn into an unallocated space and be automatically merged with other unallocated space that is next to it if have. Now you can right-click on C: drive and "Extend Volume" option is available.
Solution 2 for reason 2: Use a third-party application to merge the partitions, e.g. AOMEI Partition Assistant Server Edition.