How to extend a shared disk in a windows server cluster environment ?

If you need to extend a existing shared disk within a cluster environment please use the following KBs to safe you any pain :

How to Extend the Disk Space of an Existing Shared Disk with Windows Clustering -  https://support.microsoft.com/kb/263590

How to extend the partition of a cluster shared disk - https://support.microsoft.com/kb/304736