While trying to extend a dynamic disk formatted in ReFS on Windows Server 2022 or 2019, you might encounter the following error message: There is not enough space available on the disk to complete this operation.

To resolve this issue, you can perform the following steps:

• Go to Action ▹ Rescan Disks and try again.

This simple step has been found to work in our case.

1. Ensure that all disk operations are performed during a maintenance window to avoid any disruptions.
2. If the problem persists, consider checking for any software updates or patches that might address this issue.

• https://learn.microsoft.com/en-us/windows-server/storage/disk-management/overview-of-disk-management