Input the following commands and hit Enter after each one. Close all programs running on the disk before converting this disk to GPT. Windows Server Disk Management and Diskpart can help you to convert disk to GPT, but you need to remove all partitions on the disk at first. You can back up the disk at first if you have important files on it. In such circumstance, you can apply Diskpart to convert disk to GPT. If there are multiple partitions on the disk that needs converting to GPT, it is a little bit bothering using Disk Management to delete one by one.

At the same time, you can find out that the option of Convert to GPT disk grayed out. When you need to convert MBR disk beyond 3TB to dynamic disk, the option of Convert to dynamic disk will be greyed out. Prorogata la scadenza delle linee b e c del

However, you may find out the option of Convert to Dynamic Disk disabled in Windows Server after you right click the disk in Disk Management. In order to experience the advanced features of dynamic disk, you may want to convert a disk to dynamic from basic.

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