How to Repair Synology Volume when receiving critical error

I've had the same issue on my DS-216+. First, one (relatively new, running-okay) drive is reported as Crashed because 'The system detected that a drive reset command has failed', so the Volume becomes Critical and read-only. The crashed drive

您可以將 Synology NAS 開機並能登入 DSM，但因爲硬碟發生錯誤，以致無法透過 File Station 讀取 Synology NAS 上的資料。 請聯絡當地的資料救援公司以尋求協助。

Go to Storage Manager to remove the storage pool of the crashed volume. Run a memory test on your Synology NAS (learn more). If the test result is not Normal or successful, please replace the memory module. If you are using a non-Synology memory module, p

To fix a drive failure issue on your Synology NAS, power down the unit, remove the crashed disk, and restart while deleting old volumes associated with that disk.

您可以將 Synology NAS 開機並能登入 DSM，但因爲硬碟發生錯誤，以致無法透過 File Station 讀取 Synology NAS 上的資料。 請聯絡當地的資料救援公司以尋求協助。

In this video, I will show you the step by step process I went through when the hard drive and volume crashed on my Synology NAS.