problem adding storage to instance

It appears you're experiencing an issue with the persistence of your additional storage after restarting your EC2 instance. This is a common problem when working with EC2 instances and additional storage volumes. Here's what might be happening and how you can address it:

1. Temporary vs. Persistent Storage: The additional drive you created might be using instance store storage rather than an Elastic Block Store (EBS) volume. Instance store volumes are temporary and do not persist after an instance is stopped or terminated.

2. EBS Volume Attachment: If you did create an EBS volume, it's possible that it's not set to automatically attach to your instance on startup. You'll need to ensure that the volume is configured to attach automatically.

3. Drive Letter Assignment: Windows doesn't always maintain drive letter assignments across restarts, especially for non-boot volumes.

To resolve this issue:

1. Verify that you're using EBS volumes for your additional storage. These persist independently of the instance lifecycle.

2. In the EC2 console, check your instance's details and ensure that all desired EBS volumes are attached and set to attach automatically on instance start.

3. If the volumes are attached but not appearing in Windows:

   • Open Disk Management (as you've done)
   • Look for disks marked as "Offline"
   • Right-click on these disks and select "Online"
   • If necessary, assign a drive letter

4. For future reference, you can use the EC2 User Data script to automatically mount volumes and assign drive letters on instance start.

5. If you're repeatedly creating new volumes, be cautious as this can lead to unnecessary costs. Make sure to delete any unneeded volumes.

Remember, extending the boot volume (Disk 0) often requires the instance to be stopped first, which is why that option might be greyed out.

If you continue to have issues, you may need to review your EC2 instance's configuration in the AWS console to ensure all volumes are correctly attached and persisting across restarts.
Sources
adding storage to an instance | AWS re:Post

The EBS volumes whether allocated or not will stay attached to the EC2. If you want to delete it, you can delete it from EC2 console or CLI. In EC2 console, choose the EC2, then storage and find the volume. Open the volume in a new tab, and detach from EC2 and then delete. You need to be careful on selecting the correct volume to delete as you have a number of these with same volume size.

Also, for Windows, the EBS volume need to be initialised - https://learn.microsoft.com/en-us/windows-server/storage/disk-management/initialize-new-disks