Hi [NAME] C,   Here is my solution: After reading a lot of options and recommendations that don't work for me I decide to reset both RAID Controllers, first the one that was replaced, RAID Controller Module in Enclosure 0, Slot 1, and after verifying that everything works Ok did the same process on RAID Controller Module in Enclosure 0, Slot 0. Here are the steps followed:   [IMAGE] The yellow RAID Controller Module in Enclosure 0, Slot 1 (The one replaced) Another option is:   Then I did the same procedure for the other RAID Controller (Enclosure 0, Slot 0) [IMAGE] The green RAID Controller Module in Enclosure 0, Slot 0  Another option is: After this process went to Recovery Guru press Recheck and clears the message showing no failures [IMAGE] I hope this process helps other people. 
Hi, The recovery guru recommends replacing the RAID Controller Module because one of the controllers failed. I bought one from a company and installed it in the PowerVault 3220i but the Recovery Guru has the error Cache Backup Device Failed. I verified on the EMS The only difference is on Cache Backup Device is: Module 0     Module 1     Does the Capacity need to be the same? or bring me the steps to solve this problem, please. Thanks Arn
PowerVault 3220i controller replaced but continue with Cache Backup Device 
Failed