New
#11
Still waiting for the screenshot.
With the number of partitions you already have, you might be prompted to convert to Dynamic Disk which is not desireable, requiring us to have to help you convert it back. If there are only three Primary partitions now, it should offer to make a Logical partition which is fine.
But why not post back the screenshot so we can advise you with confidence, as we have thousands of others here without a single failure.
We use free Partition Wizard bootable CD here for operations which Disk Management cannot do, but this should be able to be handled by Disk Mgmt.